2012学年嘉定区高三年级第三次质量调研数学试卷(理) 参考答案与评分标准
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高中数学学习材料马鸣风萧萧*整理制作2014学年嘉定区高三年级第三次质量调研数学试卷(理)考生注意:本试卷共有23道试题,满分150分,考试时间120分钟.解答必须写在答题纸上的规定区域,写在试卷或草稿纸上的答案一律不予评分.一.填空题(本大题有14题,满分56分)考生应在答题纸相应编号的空格内直接填写结果,每个空格填对得4分,否则一律得零分.1.已知复数i a z +=1,i z -=12(其中R ∈a ,i 为虚数单位),若21z z ⋅为纯虚数,则a 的值为___________.2.函数)21lg(xy -=的定义域是_____________.3.已知直线l 的一个法向量为)3,1(-=n,则直线l 的倾斜角=α__________. 4.函数xxx x y cos cos cos 2sin 2-=的最大值是_________________.5.已知等差数列}{n a 的前n 项和为n S ,且62S S =,14=a ,则=5a __________. 6.若关于x 的不等式4632>+-x ax 的解集为1{<x x 或}b x >,则实数b 的值为______.7.已知双曲线C 的渐近线方程为x y 2±=,且与椭圆1244922=+y x 有相同的焦点,则双曲 线C 的标准方程为______________________. 8.在极坐标系数中,曲线13cos =⎪⎭⎫⎝⎛+πθρ与13sin =⎪⎭⎫ ⎝⎛+πθρ的交点到极点的距离为 _____________.9.按下图所示的程序框图运算:若输入17=x ,则输出的x 值是 .是开始 输入x 0←k 12+←x x 1+←k k否结束115>x 输出x10.设甲、乙两个圆柱的底面积分别为1S 、2S ,体积分别为1V 、2V ,若它们的侧面积相等,且9421=S S ,则=21V V___________. 11.甲口袋中有3个白球、2个黑球,乙口袋中有2个白球、3个黑球,从这两个口袋中分 别摸出2个球,则4个球为2个白球2个黑球的概率是___________(结果用最简分数 表示). 12.已知正方形ABCD 的边长为1,记以A 为起点,其余顶点为终点的向量分别为1a ,2a ,3a .若}3,2,1{,∈j i 且j i ≠,则CD a a j i ⋅+)(的所有可能取值的集合为_______.13.已知}{n a 是递增的等比数列,且132-=+a a ,那么首项1a 的取值范围是________. 14.定义在R 上的偶函数)(x f 满足:)()2(x f x f -=-,且在]0,1[-上是增函数,有下列4个关于)(x f 的判断:①)(x f 是周期函数;②0)5(=f ;③)(x f 在]2,1[上是减 函数;④)(x f 在]1,2[--上是减函数.其中正确的判断是_________________(写出 所有正确判断的序号).二.选择题(本大题共有4题,满分20分)每题有且只有一个正确答案,考生应在答题纸的相应编号上,将代表答案的小方格涂黑,选对得5分,否则一律得零分.15.若非零向量a ,b 满足||||b a =,b b a ⊥+)2(,则a 与b的夹角大小为…………( )A .︒30B .︒60C .︒90D .︒12016.已知底面边长为1,侧棱长为2的正四棱柱的各顶点均在同一个球面上,则该球的表面积为…………………………………………………………………………………( )A .π4B .π3C .π2D .π 17.定义在R 上的函数)(x f 满足⎩⎨⎧>---≤-=,0,)2()1(,0,)1(log )(2x x f x f x x x f 则)2015(f 的值为…………………………………………………………………………………………( ) A .1- B .0 C .1 D .218.设R ∈n m ,,直线01=-+ny mx 与x 轴交于点A ,与y 轴交于点B ,若直线l 与圆322=+y x 相切,则△OAB (O 为坐标原点)面积的最小值是…………………( )A .2B .3C .4D .5三.解答题(本大题共有5题,满分74分)解答下列各题必须在答题纸相应编号的规定区域内写出必要的步骤.19.(本题满分12分)本题共有2个小题,第1小题满分6分,第2小题满分6分.已知函数x xx xx f sin 2cos sin 2cos )(++=.(1)求)(x f 的定义域和最小正周期; (2)在锐角△ABC 中,若2)(=A f ,2=a ,6=b ,求C ∠的大小及边c 的值.20.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.如图,在四棱锥ABCD P -中,⊥PA 底面ABCD ,AD AB ⊥,4=+AD AB ,2=CD ,︒=∠45CDA .(1)若1=PA ,求四棱锥ABCD P -体积V 的最大值; (2)若AB PA =,且PB 与平面PCD 所成的角为︒30,求AB 的长.21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.已知函数)3(1)(b ax f x-=的图像过点)2,1(A 和)5,2(B . (1)求a 、b 的值及)(x f 的反函数)(1x f -的解析式;(2)当]2,1[∈x 时,求函数)(21)14(log )(19x f x x H --+=的值域.PA B DC22. (本题满分16分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分6分.设抛物线Γ:py x 22=(0>p )的焦点为F ,过点F 作斜率为1的直线与该抛物线交于A 、B 两点,A 、B 在x 轴上的射影分别为D 、C ,且梯形ABCD 的面积为212.(1)求抛物线Γ的方程;(2)过点)2,0(M 任作一直线与抛物线Γ交于P 、Q 两点,过Q 作y 轴的平行线与直线PO 相交于点R (O 为坐标原点),证明:动点R 在定直线上.(3)任作一条不与坐标轴垂直的直线l ,l 与抛物线Γ有且只有一个公共点,若l 与直线2=y 交于点1N ,与(2)中的定直线交于点2N .证明:2122||||MN MN -为定值,并求此定值.23. (本题满分18分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分8分.已知等比数列}{n a 的首项21=a ,公比为q (q 为正整数),且满足33a 是18a 与5a 的等差中项.数列}{n b 满足023)(22=++-n n b n b t n (R ∈t ,*N ∈n ). (1)求数列}{n a 的通项公式;(2)试确定t 的值,使得数列}{n b 为等差数列;(3)当}{n b 为等差数列时,对任意正整数k ,在k a 与1+k a 之间插入k b 个2,得到一个新数列}{n c .设n T 是数列}{n c 的前n 项和,试求2n T (*N ∈n )的表达式.2014学年嘉定区高三年级第三次质量调研 数学试卷(理)参考答案与评分标准一.填空题(本大题有14题,满分56分)1.1- 2.)0,(-∞ 3.6π4.12+ 5.1- 6.2 7.120522=-y x 8.2 9.143 10.32 11.5021 12.}2,1{-- 13.⎪⎭⎫ ⎝⎛-∞-21, 14.①②③二.选择题(本大题共有4题,满分20分)15.D 16.A 17.C 18.B三.解答题(本大题共有5题,满分74分)19.(本题满分12分)本题共有2个小题,第1小题满分6分,第2小题满分6分.(1)要使得函数)(x f 有意义,只需0cos sin ≠+x x 即可,即1tan -≠x ,……(1分) 所以,函数)(x f 的定义域为⎭⎬⎫⎩⎨⎧∈-≠Z k k x x ,4ππ.………………(3分) x x x x x x x x x x x x f cos sin sin 2cos sin sin cos sin 2cos sin 2cos )(22+=++-=++=⎪⎭⎫ ⎝⎛+=4sin 2πx ,……………………(5分)所以,)(x f 的最小正周期π2=T . ……………………………………(6分) (2)由24sin 2)(=⎪⎭⎫ ⎝⎛+=πA A f ,得14sin =⎪⎭⎫ ⎝⎛+πA ,故24ππ=+A ,4π=A , ……………………………………………………(1分)由正弦定理,AaB b sin sin =,即4sin 2sin 6π=B ,得23sin =B , ……………(3分)因为⎪⎭⎫ ⎝⎛∈2,0πB ,所以3π=B ,所以12534ππππ=⎪⎭⎫ ⎝⎛+-=C , ……………(4分)由正弦定理,AaC c sin sin =,得1342622125sin 22+=+⋅==πc .…(6分)20.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分. (1)在底面ABCD 内,作AD CE ⊥,E 为垂足, 因为2=CD ,︒=∠45CDA 所以△CDE 是等腰直角三角形,1==ED CE ,故3=+AE AB , …………(2分) 所以,CDE ABCE ABCD S S S ∆+=21)1(2121)(21+⋅+=⋅+⋅+=AE AB ED CE AE CE AB 21)3)(1(21+-+=AB AB 25)1(212+--=AB . ……………………(4分) 所以,当且仅当1=AB 时,ABCD S 取最大值25.…(5分)此时,四棱锥ABCD P -体积V 取最大值,且65max =V .……………………………………(6分)(2)以A 为坐标原点,AB 、AD 、AP 所在直线分别为x 轴、y 轴、z 轴建立空间直角坐标系, ………………………………………………………………(1分) 设a PA AB ==,则)0,0,(a B ,),0,0(a P ,)0,3,1(a C -,)0,4,0(a D -, 所以,)0,1,1(-=CD ,),4,0(a a PD --=,),0,(a a PB -= …………(2分)设平面PCD 的一个法向量为),,(z y x n = ,则由⎪⎩⎪⎨⎧⊥⊥,,PD n CD n 得⎩⎨⎧=--=+-,0)4(,0z a y a y x取a x =,则a y =,a z -=4,)4,,(a a a n -=, …………………………(4分)因为PB 与平面PCD 所成的角为︒30,所以||||||30sin n PB n PB ⋅⋅=︒, ……………(6分)即21)4(2|42|22222=-++⋅-a a a a a a ,解得54=a 或4=a (舍去). 所以,AB 的长为54. ………………………………(8分) 21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.(1)由题意得,⎪⎪⎩⎪⎪⎨⎧-=-=,)3(15,)3(122b a b a解得⎩⎨⎧-==,1,2b a ………………(2分)所以)13(21)(+=x x f .由)13(21+=x y ,得123-=y x,故31>y . ……(4分))12(log 3-=y x , ……………………………………………………(5分)P A B DC E所以反函数)12(log )(31-=-x x f(21>x ). ……………………………(6分) (2)1214log )12(log 21)14(log 21)(333-+=--+=x x x x x H 1232log 3-+=x ,…………………………………………………(2分)因为123-=x t 在]2,1[∈x 上是减函数,所以]3,1[∈t , ………………(5分) 所以]5,3[1232∈-+x , ………………………………(6分) 所以,函数)(x H 的值域是⎥⎦⎤⎢⎣⎡5log 21,213. …………………………………(8分)22. (本题满分16分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分6分.(1)⎪⎭⎫⎝⎛2,0p F ,由题意得,直线AB 的方程为2p x y +=,由⎪⎩⎪⎨⎧+==,2,22p x y py x 得0222=--p px x , ………………………………………………………(1分)设),(11y x A ,),(22y x B ,则p x x 221=+,221p x x -=,所以梯形ABCD 的面积||)(21|||)||(|212121x x y y CD BC AD S -⋅+=⋅+=21223223214)()(2122122121==⋅⋅=-+⋅++=p p p x x x x p x x , 解得2=p . ………………………………………………………………(3分)所以,抛物线Γ的方程为y x 42=. ………………………………………(4分) (2)由题意,设直线PQ 的方程为2+=kx y , …………………………(1分)代入y x 42=得0842=--kx x ,设),(p P y x P ,),(Q Q y x Q ,则8-=Q P x x ,…(2分)又直线PO 的方程为x x y y P P =,即x xy P 4=, …………………………(3分) 又直线QR 的方程为Q x x =,解得交点⎪⎪⎭⎫ ⎝⎛4,Q P Q x x x R ,即)2,(-Q x R .……(5分)所以,点R 在定直线2-=y 上. …………………………………………(6分) (3)由题意,直线l 的斜率存在且不为0,设直线l 的方程为b ax y +=(0≠a ),代入y x 42=,得0442=--b ax x , ……………………………………(1分)由△0=,得016162=+b a ,即2a b -=, …………………………………(2分) 所以直线l 的方程为2a ax y -=. …………………………………(3分) 分别令2=y ,2-=y ,得⎪⎭⎫ ⎝⎛+2,21a a N ,⎪⎭⎫⎝⎛--2,22a a N ,…………(4分) 所以8242||||2222122=⎪⎭⎫ ⎝⎛+-+⎪⎭⎫ ⎝⎛-=-a a a a MN MN (定值). …………(6分)23. (本题满分18分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分8分.(1)因为51386a a a +=,所以4286q q +=,解得42=q 或22=q ,……(2分) 因为q 是正整数,所以2=q ,又21=a ,所以n n a 2=(*N ∈n ). …………(4分)(2)由023)(22=++-n n b n b t n ,得2322--=n tn n b n ,所以421-=t b ,t b 4162-=,t b 2123-=,则由2312b b b =+,得3=t . ……………………………………(3分) 当3=t 时,n b n 2=,由21=-+n n b b (常数). …………………………(5分)所以,3=t 时,使得数列}{n b 是首项为2,公差为2的等差数列.………………(6分)(3)由(2)知k b k 2=, ……………………………………………………(1分) 由题意,数列}{n c 是在原来的数列}{n a 在k a 与1+k a 之间插入k 2个2而得到.所以,211==a c ,2242==a c ,3392==a c , ……………………………………(2分)一般地,在数列}{n c 中,在项nn a 2=前共插入)1()1(2642-=-++++n n n 个2,故n n a 2=在数列}{n c 中的项数为2)1(n n n n =-+.即n n n a c 22==. ………………(5分)所以,)1(221)21(2)(2)222(12122-⋅+--=++++++=-n n b b b T n n nn 222221--+=+n n n . …………………………………………………………(8分)。
2011学年嘉定区高三年级第三次模拟考试数学试卷(文科)(2012年5月14日)考生注意:本试卷共23题,满分150分,考试时间120分钟.一.填空题(本大题满分56分)本大题共有14题,只要求直接填写结果,每个空格填对得4分,否则一律得零分.1.设集合},1{R x x x A ∈<=,},4{2R x x x B ∈<=,则=B A ___________. 2.设a 、R b ∈,i 为虚数单位,若i b i i a +=+)(,则复数bi a z +=的模为______. 3.函数x x y 2sin cos 2-=的最小正周期为_____________. 4.函数1)(-=x x f (1≥x )的反函数=-)(1x f_____________.5.系数矩阵为⎪⎪⎭⎫ ⎝⎛2312,解为⎪⎪⎭⎫ ⎝⎛=⎪⎪⎭⎫ ⎝⎛21y x 的一个线性方程组是_______________. 6.已知向量)1,1(-=k a,)2,(-=k b ,若b a ⊥,则实数k 的值为_____________.7.若一个圆锥的主视图是边长为3的等边三角形,则该圆锥的侧面积是_____________.8.若a ,b ,c 成等比数列,则函数c bx axx f ++=2)(的图像与x 轴交点的个数为_______.9.设⎩⎨⎧<+-≥--=.0,42,0,12)(2x x x x x x f 则不等式2)(>x f 的解集为______________________.10.执行如下图所示的程序框图,那么输出的S 值为_____________.11.已知动圆圆心在抛物线x y 42=上,且动圆恒与直线1-=x 相切,则此动圆必过定点________________.12.从5名男生和2名女生中选出3人参加交通安全志愿者活动,则选出的3人中既有男生又有女生的概率是____________.13.实数x 、y 满足⎪⎩⎪⎨⎧≤+-≤≥,,12,1m y x x y y 如果目标函数y x z -=的最小值为1-,则实数m 的值为_________________.14.已知函数11)(+=x x f ,点n A 为函数)(x f 图像上横坐标为n (*N n ∈)的点,O 为坐标原点,向量)0,1(=e.记n θ为向量n OA 与e 的夹角,则=+++∞→)t a n t a n (t a n lim 21n n θθθ ___________.二.选择题(本大题满分20分)本大题共有4题,每题都给出代号为A 、B 、C 、D 的四个结论,其中有且仅有一个结论是正确的,必须把正确结论的代号写在题后的圆括号内,选对得5分,不选、选错或者选出的代号超过一个(不论是否都写在圆括号内),一律得零分.15.“1tan =α”是“)(42Z k k ∈+=ππα”的…………………………………………( )A .充分非必要条件B .必要非充分条件C .充分必要条件D .既非充分又非必要条件16.下列命题中正确的是……………………………………………………………………( )A .若bc ac >,则b a >B .若22b a >,则b a >C .若b a >,则b a > D .若ba 11<,则b a >17.如图,四棱锥ABCD P -的底面是︒=∠60BAD 的菱形,且PC PA =,BD PB =,则该四棱锥的主视图(主视图投影平面与平面PAC 平行)可能是…………………( )A .B .C .D .18.若对于任意实数m ,关于x 的方程0)12(log 22=-++m x ax 恒有解,则实数a 的取值范围是……………………………………………………………………………………( )A .)1,(-∞B .]1,0(C .]1,0[D .)1,0(C ABDP三.解答题(本大题满分74分)本大题共有5题,解答下列各题必须写出必要的步骤. 19.(本题满分12分)本题共有2个小题,第1小题满分5分,第2小题满分7分.如图,在正三棱柱111C B A ABC -中,2=AB ,41=AA .(1)求三棱柱111C B A ABC -的表面积S ;(2)设E 为棱1BB 的中点,求异面直线E A 1与BC 所成角的大小(结果用反三角函数值表示). 解:(1) (2)20.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分. 如图,在平面直角坐标系xOy 中,M 、N 分别是椭圆12422=+yx的顶点.过坐标原点的直线交椭圆于A 、B 两点,其中A 在第一象限.过点A 作x 轴的垂线,垂足为C .设直线AB 的斜率为k .(1)若直线AB 平分线段MN ,求k 的值;(2)当2=k 时,求点A 到直线BC 的距离. 解:(1)E CBAA 1B 1C 1(2)21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.如图,角θ的始边OA 落在x 轴上,其始边、终边分别与单位圆交于点A 、C(20πθ<<),△AOB 为等边三角形.(1)若点C 的坐标为⎪⎭⎫⎝⎛53,54,求BOC ∠cos 的值; (2)设2||)(BC f =θ,求函数)(θf 的解析式和值域. 解:(1) (2)小题满分6分.设向量)2,(x a =,)12,(-+=x n x b(*N n ∈),函数b a y⋅=在]1,0[∈x 上的最小值与最大值的和为n a ,又数列}{n b 满足11=b ,121109-⎪⎭⎫ ⎝⎛=+++n n b b b .(1)求证:1+=n a n ;(2)求数列}{n b 的通项公式;(3)设n n n b a c ⋅-=,试问数列}{n c 中,是否存在正整数k ,使得对于任意的正整数n ,都有k n c c ≤成立?若存在,求出所有满足条件的k 的值;若不存在,请说明理由. 解:(1) (2) (3)小题满分7分.已知函数b xax x f ++=)((0≠x ),其中a 、b 为实常数. (1)若方程13)(+=x x f 有且仅有一个实数解2=x ,求a 、b 的值;(2)设0>a ,),0(∞+∈x ,写出)(x f 的单调区间,并对单调递增区间用函数单调性定义进行证明;(3)若对任意的⎥⎦⎤⎢⎣⎡∈2,21a ,不等式10)(≤x f 在⎥⎦⎤⎢⎣⎡∈1,41x 上恒成立,求实数b 的取值范围.解:(1)(2)(3)2011学年嘉定区高三年级第三次模拟考试数学试卷(文科)参考答案与评分标准一.填空题(每小题4分,满分56分)1.}12{<<-x x ;2.2;3.π;4.12+x (0≥x );5.⎩⎨⎧=+=+.723,42y x y x ;6.1-或2;7.29π;8.0;9.),3()0,(∞+-∞ ;10.2550;11.)0,1(;12.75;13.5;14.1.二.选择题(每小题5分,满分20分) 15.B ;16.C ;17.B ;18.C .三.解答题19.(第1小题5分,第2小题7分,满分12分) (1)32432=⋅=∆ABC S ,……(1分) 2446=⨯=侧S . ……(3分)所以侧S S S ABC +=∆22432+=. ……(5分) (2)取1CC 中点F ,连结EF 、F A 1.因为EF ∥BC ,所以EF A 1∠就是异面直线E A 1与BC 所成角(或其补角).……(7分)在△EF A 1中,2=EF ,2211==F A E A ,42cos 1=∠EF A .…………(11分)所以异面直线E A 1与BC 所成角的大小为42arccos.…………(12分)20.(第1小题6分,第2小题8分,满分14分) (1)由题设知,2=a ,2=b ,故)0,2(-M ,)2,0(-N ,所以线段MN 中点的坐标为⎪⎪⎭⎫⎝⎛--22,1.………………(3分) 由于直线AB 平分线段MN ,故直线AB 过线段MN 的中点,又直线AB 过坐标原点,所以22122=--=k .…………(6分)FE CB AA 1B 1C 1(2)当2=k 时,直线AB 的方程为x y 2=,由⎪⎩⎪⎨⎧=+=,124,222yx x y 解得32±=x ,…(8分) 从而A 点的坐标是⎪⎭⎫ ⎝⎛34,32,B 点的坐标为⎪⎭⎫ ⎝⎛--34,32,……(10分) 于是C 点的坐标为⎪⎭⎫⎝⎛0,32.…(11分)所以直线BC 的方程为032=--y x .…(12分)所以点A 到直线BC 的距离为3222343432=--=d .…………(14分)21.(第1小题6分,第2小题8分,满分14分) (1)由题意,3πθ+=∠BOC ,因为点C 的坐标为⎪⎭⎫⎝⎛53,54, 所以53sin =θ,54cos =θ,…………(3分) 所以10334235321543cos cos -=⋅-⋅=⎪⎭⎫⎝⎛+=∠πθBOC .…………(6分) (2)解法一:在△BOC 中,由余弦定理,BOC OC OB OC OB BC ∠-+=cos ||||2||||||222,……(7分)所以⎪⎭⎫ ⎝⎛+-=3cos 22)(πθθf .…………(10分) 因为20πθ<<,所以⎪⎭⎫ ⎝⎛∈+65,33πππθ,……(11分) 所以)32,1()(+∈θf .…………(13分)因此,函数⎪⎭⎫⎝⎛+-=3cos 22)(πθθf (20πθ<<),)(θf 的值域是)32,1(+.(14分) 解法二:由题意,⎪⎪⎭⎫⎝⎛-23,21B ,)sin ,(cos θθC ,……(7分) 所以⎪⎭⎫ ⎝⎛-+=-+=⎪⎪⎭⎫⎝⎛++⎪⎭⎫⎝⎛-=6s22)c s 3(223s21co||222πθθθθθBC ……………………………………(10分)因为20πθ<<,所以⎪⎭⎫⎝⎛-∈-3,66πππθ,…(11分)所以)32,1()(+∈θf .(13分)所以,函数⎪⎭⎫⎝⎛++=6sin 22)(πθθf (20πθ<<),)(θf 的值域是)32,1(+.(14分)22.(第1小题4分,第2小题6分,第3小题6分,满分16分) (1)由已知,2)4()12(2)(2-++=-++=x n x x n x x y ……(2分) 而函数y 在]1,0[∈x 上是增函数,……(3分) 所以12412+=-+++-=n n a n .……(4分) (2)因为121109-⎪⎭⎫ ⎝⎛=+++n n b b b ,所以2121109--⎪⎭⎫ ⎝⎛=+++n n b b b (2≥n ),………………(6分)两式相减,得2109101-⎪⎭⎫⎝⎛⋅-=n n b ()2≥n .…………(8分)所以,数列}{n b 的通项公式为⎪⎩⎪⎨⎧⎪⎭⎫ ⎝⎛⋅-==-.109101,1,12n n n b …………(10分)(3)因为02111<-=-=b a c ,01091012>⎪⎭⎫⎝⎛⋅+=-n n n c (2≥n ),……(12分) 由题意,k c 为}{n c 的最大项,则2≥k , 要使k c 为最大值,则⎩⎨⎧≥≥+-,,11k kk k c c c c ……(13分)即⎪⎪⎩⎪⎪⎨⎧⎪⎭⎫⎝⎛⋅+≥⎪⎭⎫ ⎝⎛⋅+⎪⎭⎫ ⎝⎛⋅≥⎪⎭⎫⎝⎛⋅+----123210910210910110910109101k k k k k k kk ……(14分)解得9=k 或8=k . …………(15分)所以存在8=k 或9,使得k n c c ≤对所有*N n ∈成立.…………(16分)23.(第1小题5分,第2小题6分,第3小题7分,满分18分) (1)由已知,方程13+=++x b xa x 有且仅有一个解2=x ,因为0≠x ,故原方程可化为0)1(22=--+a x b x ,…………(1分)所以⎩⎨⎧=+-=--08)1(02102a b b a ,…………(3分)解得8-=a ,9=b .……(5分)(2)当0>a ,0>x 时,)(x f 在区间),0(a 上是减函数,在),(∞+a 上是增函数.…………(7分)(每个区间1分)证明:设),(,21∞+∈a x x ,且21x x <,112212)()(x a x x a x x f x f --+=-212112)(x x a x x x x -⋅-=,因为),(,21∞+∈a x x ,且21x x <,所以012>-x x ,a x x >21,即a x x >21, 所以0)()(12>-x f x f .………………(10分) 所以)(x f 在),(∞+a 上是增函数.…………(11分)(3)因为10)(≤x f ,故⎥⎦⎤⎢⎣⎡∈1,41x 时有10)(max ≤x f ,……(12分)由(2),知)(x f 在区间⎥⎦⎤⎢⎣⎡1,41的最大值为⎪⎭⎫⎝⎛41f 与)1(f 中的较大者.……(13分) 所以,对于任意的⎥⎦⎤⎢⎣⎡∈2,21a ,不等式10)(≤x f 在⎥⎦⎤⎢⎣⎡∈1,41x 上恒成立,当且仅当 ⎪⎩⎪⎨⎧≤≤⎪⎭⎫ ⎝⎛10)1(1041f f ,即⎪⎩⎪⎨⎧-≤-≤a b a b 94439对任意的⎥⎦⎤⎢⎣⎡∈2,21a 成立.…………(15分) 从而得到47≤b . …………(17分)所以满足条件的b 的取值范围是⎥⎦⎤⎝⎛∞-47,. …………(18分)。
上海市嘉定区-高三第三次质量调研数学试卷(理科)5月16日题号一二三总分1—1415—18 19 20 21 22 23 得分考生注意:1.答卷前,考生务必将学校、班级、姓名、考号等在试卷相应位置填写清楚.2.本试卷共有23道试题,满分150分,考试时间120分钟.请考生用黑色钢笔或圆珠笔将答案直接填写在试卷上.一.填空题(本大题共有14题,每小题4分,满分56分)将结果填写在题目的横线上. 1.设集合}35{<<-=x x A ,}42{<<-=x x B ,则=B A ___________.2.已知向量)cos ,(sin x x a =,)2,1(-=b ,且b a ⊥,则=x tan _________.3.函数xxy 21lg -=的定义域是______________.4.已知二元一次方程组⎩⎨⎧=+=+222111c y b x a c y b x a 的增广矩阵是⎪⎪⎭⎫⎝⎛-311111,则此方程组的解是 _________________.5.在等差数列}{n a 中,若公差0≠d ,且2a ,3a ,6a 成等比数列,则公比=q ________.6.若关于x 的方程0122=--ax ax 有且仅有一个实数根,则实数=a ________.7.设*N n ∈,n x )12(+展开式各项系数之和为n a ,nx )13(+展开式各项系数之和为n b ,则=++++∞→1132lim n n n n n b a b a __________. 8.函数⎪⎭⎫ ⎝⎛-⎪⎭⎫⎝⎛+=4cos 4cos )(ππx x x f 的图像上相邻 两个对称中心的距离是___________.9.在极坐标系中,将圆θρcos 2a =(0>a )的圆心绕极点按逆时针方向旋转2π,所得圆的极坐标方程为___________________.10.执行如图所示的程序框图,若输入的5.10-=x , 则输出y 的结果为 .11.已知长方体的三条棱长分别为1,1,2,并且该长方体的八个顶点都在一个球的球面上,则此球的表面积为____________.12.某班从5名班(其中男生3人,女生2人)中选3人参加学校学生会的竞选.设所选3人中女生人数为ξ,则随机变量ξ的方差=ξD ___________.13.椭圆12922=+y x 的焦点为1F 、2F ,点P 在椭圆上,若4||1=PF ,则=⋅21PF PF ________________.14.已知集合M 是满足下列两个条件的函数)(x f 的全体:①)(x f 在定义域上是单调函数;②在)(x f 的定义域内存在闭区间],[b a ,使)(x f 在],[b a 上的值域为⎥⎦⎤⎢⎣⎡2,2b a .若函数m x x g +-=1)(,M x g ∈)(,则实数m 的取值范围是________________.二.选择题(本大题共有4题,每小题5分,满分20分)请将正确选项的字母填写在题后括号内. 15.若函数)(x f 的定义域是R ,则“0)0(=f ”是“)(x f 为奇函数”的…………( )A .充分非必要条件B .必要非充分条件C .充分必要条件D .既非充分又非必要条件 16.抛物线2x y =的焦点坐标是…………………………………………………………( )A .⎪⎭⎫⎝⎛0,41 B .⎪⎭⎫ ⎝⎛0,21 C .⎪⎭⎫ ⎝⎛41,0 D .⎪⎭⎫⎝⎛21,0 17.已知M 是△ABC 内的一点,且32=⋅AC AB ,030=∠BAC ,若△MBC ,△MCA 和△MAB 的面积分别为21,x ,y ,则y x 41+的最小值是…………………( )A .20B .18C .16D .918.已知函数⎪⎩⎪⎨⎧>+-≤<=4,24140,|log |)(4x x x x x f ,若a 、b 、c 的值互不相等,且)()()(c f b f a f ==,则abc的取值范围是……………………………………………( )A .)4,1(B .)5,2(C .)6,3(D .)8,4(三.解答题(本大题满分74分)本大题共有5题,解答各题必须写出必要的步骤. 19.(本题满分12分)本题共有2个小题,第1小题满分5分,第2小题满分7分.设复数i z +=αsin 1,i m m z )cos (2α-+=,其中i 为虚数单位,)2,0[πα∈,R m ∈且21z z =. (1)求α的值;(2)设ααsin cos i t +=,求121)(-++++=n t t t t f (*N n ∈).否开始 输入x0>x2+←x xx y 2←输出y结束是第10题图20.(本题满分14分)本题共有2个小题,第1小题满分7分,第2小题满分7分在三棱锥BCD A -中,⊥AD 面BCD ,CD BD ⊥,2==BD AD ,32=CD ,E 、F 分别是AC 和BC 的中点. (1)求三棱锥CDF E -的体积;(2)求二面角C DF E --的大小(用反三角函数值表示).21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分火山喷发后,会在喷发区及周边地区地面上堆积起大量火山灰.在一次火山喷发停止后对地面火山灰的堆积量进行测量,设定距离喷口中心50m 内的圆形区域为第1区,距离喷口中心50m 至100m 的圆环形区域为第2区,距离喷口中心100m 至150m 的圆环形区域为第3区,…,距离喷口中心)1(50-n m 至n 50m 的圆环形区域为第n 区….测得第1区火山灰堆积重量平均为1000kg 2/m ,第2区火山灰每平方米的平均重量比第1区减少%2,第3区比第2区又减少%2,…,依此类推(题中*N n ∈,m 表示长度单位米,kg 表示重量单位千克).(1)若第n 区平均每平方米火山灰的堆积重量为n a (kg ),写出n a 的表达式; (2)第几区内的火山灰的总重量最大?22.(本题满分16分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分6分如图,已知椭圆1222=+y x 的左右焦点分别为1F 、2F ,椭圆的下顶点为A ,点P 是椭圆上任意一点,E DAF圆M 是以2PF 为直径的圆.(1)若圆M 过原点O ,求圆M 的方程;(2)当圆M 的面积为8π时,求PA 所在直线的方程;(3)写出一个定圆的方程,使得无论点P 在椭圆的什 么位置,该定圆总与圆M 相切.请写出你的探究过程.23.(本题满分18分)本题共有3个小题,第1小题满分6分,第2小题满分5分,第3小题满分7分已知R k ∈,0>a 且1≠a ,0>b 且1≠b ,函数xxb k a x f ⋅+=)(.(1)如果实数a 、b 满足1>a ,1=ab ,试判断函数)(x f 的奇偶性,并说明理由; (2)设01>>>b a ,0≤k ,判断函数)(x f 在R 上的单调性并加以证明;(3)若2=a ,21=b ,且0>k ,问函数)(x f 的图像是不是轴对称图形?如果是,求出函数)(x f 图像的对称轴;如果不是,请说明理由.上海市嘉定区-高三第三次质量调研 数学试卷(理科) 参考答案与评分标准一.填空题(本大题共有14题,每小题4分,满分56分) 1.}32{<<-x x ;2.2;3.⎪⎭⎫ ⎝⎛21,0;4.⎩⎨⎧==12y x ;5.3;6.1-;7.43; 8.2π;9.θρsin 2a =;10.3;11.π6;12.259;13.4-;14.⎥⎦⎤⎝⎛21,0.二.选择题(本大题共有4题,每小题5分,满分20分) 15.B ; 16.C ; 17.B ; 18.D .三.解答题(本大题满分74分)本大题共有5题. 19.(本题满分12分)本题共有2个小题,第1小题满分5分,第2小题满分7分. 解:(1)因为21z z =,所以αsin =m ,1cos =-αm ,即1cos sin =-αα,……(2分)所以224sin =⎪⎭⎫⎝⎛-πα,……(3分) 由)2,0[πα∈得⎪⎭⎫⎢⎣⎡-∈-47,44πππα,所以44ππα=-或434ππα=-,即2πα=或πα=.……(5分)(2)①当2πα=时,i t =,i i i i i t f n n--=++++=111)(2 ,……(8分)k n 4=(*N n ∈)时,0)(=t f ;14+=k n 时,1)(=t f ;当N n ∈,24+=k n 时,i t f +=1)(;当34+=k n 时,i t f =)(.……(9分)(此处分类讨论不做扣1分) ②当πα=时,1-=t ,2)1(1)1(1111)(1n n t f --=-++-+-=- ,……(12分)当n 为奇数时,1)(=t f ;当n 为偶数时,0)(=t f .(此处分类讨论不做不扣分) 20.(本题满分14分)本题共有2个小题,第1小题满分7分,第2小题满分7分解:(1)以D 为原点,以DB 、DC 、DC 所在直线 分别为x 轴、y 轴、z 轴,建立空间直角坐标系.则)0,0,0(D ,)2,0,0(A ,)1,3,0(E ,……(2分))0,3,1(F ,因为⊥AD 平面BCD ,所以平面BCD 的一个法向量为)1,0,0(=n,……(3分))1,3,0(=DE ,设点E 到平面BCD 的距离为d ,则1=⋅=DE n d , 即三棱锥CDF E -的高为1,……(4分)因为点F 是BC 的中点,所以S △S CDF 21=△3=BCD ,……(5分)所以三棱锥CDE E -的体积S V ⋅=31△33=⋅d CDF .……(7分)(2))1,3,0(=DE ,)0,3,1(=DF ,设平面DEF 一个法向量为),,(1z y x n = ,则DE n ⊥1,DF n ⊥1 ,从而01=⋅DE n ,01=⋅DF n ,即⎪⎩⎪⎨⎧=+=+0303y x z y ,……(9分) 取3-=y ,则3==z x ,)3,3,3(1-=n.……(10分) 设二面角C DF E --的大小为θ,由图形可知θ是锐角,所以721||||||cos 11=⋅=n n n nθ.……(11分)因此,二面角C DF E --的大小为721arccos.……(12分) 21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分 解:(1)由题意,{}n a 组成以1000为首项,以98.002.01=-为公比的等比数列,……(4分)所以198.01000-⨯=n n a .……(6分)(2)设第n 区的面积为n b 2m ,则)12(2500})]1(50[)50{(22-⋅=--⋅=n n n b n ππ,……(8分)则第n 区内火山灰的总重量为1)98.0()12(25001000-⋅-⋅=⋅n n n n b a π,……(10分) 设1)98.0()12(-⋅-=n n n c ,若n c 最大,则有⎩⎨⎧≥≥+-11n n n n c c c c ,即⎪⎩⎪⎨⎧⋅+≥⋅-⋅-≥⋅----nn n n n n n n )98.0()12()98.0()12()98.0()32()98.0()12(121,解得2101299≤≤n , 即5.505.49≤≤n ,……(13分)所以50=n .即第50区内的火山灰总重量最大.……(14分)22.(本题满分16分)本题共有3个小题,第1小题满分4分,第2小题满分6分,第3小题满分6分 解:(1)解法一:因为圆M 过原点O ,所以2OF OP ⊥,所以P 是椭圆的端轴顶点,P 的坐标是)1,0(或)1,0(-,于是点M 的坐标为⎪⎭⎫ ⎝⎛21,21或⎪⎭⎫ ⎝⎛-21,21, …………(2分)圆M 的方程为21212122=⎪⎭⎫ ⎝⎛-+⎪⎭⎫ ⎝⎛-y x 或21212122=⎪⎭⎫ ⎝⎛++⎪⎭⎫ ⎝⎛-y x . ……(4分)解法二:设),(11y x P ,因为圆M 过原点O ,所以2OF OP ⊥,所以02=⋅OF OP ,所以01=x ,11±=y ,点)1,0(±P ………(1分) 于是点M 的坐标为⎪⎭⎫⎝⎛21,21或⎪⎭⎫ ⎝⎛-21,21, …………(2分)圆M 的方程为21212122=⎪⎭⎫ ⎝⎛-+⎪⎭⎫ ⎝⎛-y x 或21212122=⎪⎭⎫ ⎝⎛++⎪⎭⎫ ⎝⎛-y x . ……(4分)(少一个解扣1分)(2)设圆M 的半径为r ,由题意,82ππ=r ,42=r ,所以22||2=PF …(5分)设),(11y x P ,则22)1(2121=+-y x . ………………………………………(6分) 联立⎪⎪⎩⎪⎪⎨⎧=+=+-1221)1(21212121y x y x ,解得11=x (31=x 舍去), ……………………(7分)EDCABF所以点⎪⎪⎭⎫ ⎝⎛22,1P 或⎪⎪⎭⎫ ⎝⎛-22,1P . ………………………(8分) 所以221+=PA k 或221-=PA k , …………………………(9分)所以直线PA 的方程为1221-⎪⎪⎭⎫ ⎝⎛+=x y 或1221-⎪⎪⎭⎫ ⎝⎛-=x y ………………(10分) 注:直线方程也可写成其他形式,如:022)22(=--+y x 与022)22(=---y x 等.少一个解,得4分.(3)以原点为圆心,2为半径的定圆始终与圆M 相内切.定圆的方程为222=+y x . ……………………………………(12分) 探究过程为:设圆M 的半径为r ,定圆的半径为R ,因为r PF PF PF MO -=-=-==2||212|)|22(21||21||121,所以当原点为定圆圆心,半径2=R 时,定圆始终与圆M 相内切. ……………………………(16分)23.(本题满分18分)本题共有3个小题,第1小题满分6分,第2小题满分5分,第3小题满分7分 解:(1)由已知,ab 1=,于是x x a k a x f -⋅+=)(,则xx a k a x f ⋅+=--)(,……(1分) 若)(x f 是偶函数,则)()(x f x f -=,即x x xxa k a a k a ⋅+=⋅+--,所以0))(1(=---xxaa k 对任意实数x 恒成立,所以1=k .……(3分)若)(x f 是奇函数,则)()(x f x f -=-,即)(x x x xa k a a k a --⋅+-=⋅+,所以0))(1(=++-xxaa k 对任意实数x 恒成立,所以1-=k .……(5分)综上,当1=k 时,)(x f 是偶函数;当1-=k 时,)(x f 奇函数,当1±≠k ,)(x f 既不是奇函数也不是偶函数.………………(6分)(2)因为1>a ,10<<b ,所以函数xa y =是增函数,xb y =减函数,由0≤k 知,0=⋅=xb k y 或是增函数,所以函数)(x f 在R 于是增函数.……(8分) 证明如下:设1x 、2x R ∈且21x x <,则1122)()(12x x x x b k a b k a x f x f ⋅--⋅+=-)()(1212x x x x b b k a a -+-=因为1>a ,10<<b ,21x x <,0≤k ,所以012>-x x a a,0)(12≥-x x b b k ,所以0)()(12>-x f x f ,所以函数)(x f 在R 是增函数.…………(11分) (3)xxk x f -⋅+=22)(,若函数)(x f 的图像是轴对称图形,且对称轴是直线m x =,则函数)(m x f +是偶函数,即对任意实数x ,)()(x m f x m f +=-,……(14分))()(2222x m x m x m x m k k +-+---⋅+=⋅+,化简得0)22)(22(=⋅----m m x x k ,……(16分)因为上式对任意R x ∈成立,所以022=⋅--mmk ,k m 2log 21=.……(17分) 所以,函数)(x f 的图像是轴对称图形,其对称轴是直线k x 2log 21=.……(18分)iu。
2012上海高考数学试题(理科)答案与解析一.填空题 1.计算:3-i=1+i(i 为虚数单位). 【答案】1-2i 【解析】3-i (3-i)(1-i)2-4i ===1-2i 1+i (1+i)(1-i)2. 【点评】本题着重考查复数的除法运算,首先,将分子、分母同乘以分母的共轭复数,将分母实数化即可.2.若集合}012|{>+=x x A ,}2|1||{<-=x x B ,则=B A . 【答案】 ⎪⎭⎫⎝⎛-3,21 【解析】根据集合A 210x +>,解得12x >-,由12,,13x x --<<得到,所以⎪⎭⎫⎝⎛-=3,21B A .【点评】本题考查集合的概念和性质的运用,同时考查了一元一次不等式和绝对值不等式的解法.解决此类问题,首先分清集合的元素的构成,然后,借助于数轴或韦恩图解决. 3.函数1sin cos 2)(-= x x x f 的值域是 .【答案】⎥⎦⎤⎢⎣⎡--23,25 【解析】根据题目22sin 212cos sin )(--=--=x x x x f ,因为12sin 1≤≤-x ,所以23)(25-≤≤-x f . 【点评】本题主要考查行列式的基本运算、三角函数的范围、二倍角公式,属于容易题,难度较小.考纲中明确要求掌握二阶行列式的运算性质.4.若)1,2(-=n 是直线l 的一个法向量,则l 的倾斜角的大小为 (结果用反三角函数值表示).【答案】2arctan【解析】设直线的倾斜角为α,则2arctan ,2tan ==αα.【点评】本题主要考查直线的方向向量、直线的倾斜角与斜率的关系、反三角函数的表示.直线的倾斜角的取值情况一定要注意,属于低档题,难度较小. 5.在6)2(xx -的二项展开式中,常数项等于 . 【答案】160-【解析】根据所给二项式的构成,构成的常数项只有一项,就是333462C ()160T x x=-=- .【点评】本题主要考查二项式定理.对于二项式的展开式要清楚,特别注意常数项的构成.属于中档题.6.有一列正方体,棱长组成以1为首项、21为公比的等比数列,体积分别记为 ,,,,n V V V 21,则=+++∞→)(lim 21n n V V V .【答案】78【解析】由正方体的棱长组成以1为首项,21为公比的等比数列,可知它们的体积则组成了一个以1为首项,81为公比的等比数列,因此,788111)(lim 21=-=+++∞→n n V V V . 【点评】本题主要考查无穷递缩等比数列的极限、等比数列的通项公式、等比数列的定义.考查知识较综合. 7.已知函数||)(a x e x f -=(a 为常数).若)(x f 在区间),1[+∞上是增函数,则a 的取值范围是 . 【答案】(]1,∞-【解析】根据函数,(),x a x ax ae x af x ee x a---+⎧≥⎪==⎨<⎪⎩看出当a x ≥时函数增函数,而已知函数)(x f 在区间[)+∞,1上为增函数,所以a 的取值范围为:(]1,∞- .【点评】本题主要考查指数函数单调性,复合函数的单调性的判断,分类讨论在求解数学问题中的运用.本题容易产生增根,要注意取舍,切勿随意处理,导致不必要的错误.本题属于中低档题目,难度适中.8.若一个圆锥的侧面展开图是面积为π2的半圆面,则该圆锥的体积为 . 【答案】33π 【解析】根据该圆锥的底面圆的半径为r ,母线长为l ,根据条件得到ππ2212=l ,解得母线长2=l ,1,22===r l r πππ所以该圆锥的体积为:ππ331231S 3122=-⨯==h V 圆锥.【点评】本题主要考查空间几何体的体积公式和侧面展开图.审清题意,所求的为体积,不是其他的量,分清图形在展开前后的变化;其次,对空间几何体的体积公式要记准记牢,属于中低档题.9.已知2)(x x f y +=是奇函数,且1)1(=f ,若2)()(+=x f x g ,则=-)1(g . 【答案】1- 【解析】因为函数2)(x x f y +=为奇函数,所以,3)1(,1)1(,2)1()1(==+=g f f g 所以,又1232)1()1(,3)1(-=+-=+-=--=-f g f .(1)(1).f f -=-【点评】本题主要考查函数的奇偶性.在运用此性质解题时要注意:函数)(x f y =为奇函数,所以有)()(x f x f -=-这个条件的运用,平时要加强这方面的训练,本题属于中档题,难度适中.10.如图,在极坐标系中,过点)0,2(M 的直线l 与极轴的夹角6πα=,若将l 的极坐标方程写成)(θρf =的形式,则=)(θf .【答案】)6sin(1θπ-【解析】根据该直线过点)0,2(M ,可以直接写出代数形式的方程为:)2(21-=x y ,将此化成极坐标系下的参数方程即可 ,化简得)6sin(1)(θπθ-=f .【点评】本题主要考查极坐标系,本部分为选学内容,几乎年年都有所涉及,题目类型以小题为主,复习时,注意掌握基本规律和基础知识即可.对于不常见的曲线的参数方程不作要求.本题属于中档题,难度适中.11.三位同学参加跳高、跳远、铅球项目的比赛,若每人都选择其中两个项目,则有且仅有两人选择的项目完全相同的概率是 (结果用最简分数表示). 【答案】32 【解析】一共有27种取法,其中有且只有两个人选择相同的项目的取法共有18种,所以根据古典概型得到此种情况下的概率为32. 【点评】本题主要考查排列组合概率问题、古典概型.要分清基本事件数和基本事件总数.本题属于中档题.12.在平行四边形ABCD 中,3π=∠A ,边AB 、AD 的长分别为2、1,若M 、N 分别是边BC 、CD =AN AM ⋅的取值范围是 .【答案】[]5,2【解析】以向量AB 所在直线为x 轴,以向量AD 所在直线为y 轴建立平面直角坐标系,如图所示,因为1,2==AD AB ,所以51(0,0),(2,0),(,1)(,1).22A B C D 设1515515151(,1)(), , - , - , (2,()sin ).22224284423N x x BM CN CN x BM x M x x π≤≤===+--则根据题意,有)83235,4821(),1,(xx AM x AN --==→→.【点评】本题主要考查平面向量的基本运算、概念、平面向量的数量积的运算律.做题时,要切实注意条件的运用.本题属于中档题,难度适中.13.已知函数)(x f y =的图象是折线段ABC ,其中)0,0(A 、)5,21(B 、)0,1(C , 函数)(x xf y =(10≤≤x )的图象与x 轴围成的图形的面积为 . 【答案】45 【解析】根据题意得到,110,02()11010,12x x f x x x ⎧≤≤⎪⎪=⎨⎪-+≤⎪⎩从而得到22110,02()11010,12x x y xf x x x x ⎧≤≤⎪⎪==⎨⎪-+<≤⎪⎩所以围成的面积为45)1010(10121221=+-+=⎰⎰dx x x xdx S ,所以围成的图形的面积为45 . 【点评】本题主要考查函数的图象与性质,函数的解析式的求解方法、定积分在求解平面图形中的运用.突出体现数形结合思想,本题综合性较强,需要较强的分析问题和解决问题的能力,在以后的练习中加强这方面的训练,本题属于中高档试题,难度较大. 14.如图,AD 与BC 是四面体ABCD 中互相垂直的棱,2=BC ,若c AD 2=,且a CD AC BD AB 2=+=+,其中a 、c 为常数,则四面体ABCD 的体积的最 大值是 . 【答案】13222--c a c 【解析】据题a CD AC BD AB 2=+=+,也就是说,线段CD AC BD AB ++与线段的长度是定值,因为棱AD 与棱BC 互相垂直,当ABD BC 平面⊥时,此时有最大值,此时最大值为:13222--c a c . 【点评】本题主要考查空间四面体的体积公式、空间中点线面的关系.本题主要考虑根据已知条件构造体积表达式,这是解决问题的关键,本题综合性强,运算量较大.属于中高档试题.二、选择题(20分) 15.若i 21+是关于x 的实系数方程02=++c bx x 的一个复数根,则( )A .3,2==c bB .3,2=-=c bC .1,2-=-=c bD .1,2-==c b 【答案】 B【解析】根据实系数方程的根的特点1也是该方程的另一个根,所以b i i -==-++22121,即2-=b ,c i i ==+-3)21)(21(,故答案选择B.【点评】本题主要考查实系数方程的根的问题及其性质、复数的代数形式的四则运算,属于中档题,注重对基本知识和基本技巧的考查,复习时要特别注意.16.在ABC ∆中,若C B A 222sin sin sin <+,则ABC ∆的形状是( )A .锐角三角形B .直角三角形C .钝角三角形D .不能确定 【答案】C【解析】由正弦定理,得,sin 2,sin 2,sin 2C Rc B R b A R a ===代入得到222a b c +<, 由余弦定理的推理得222cos 02a b c C ab+-=<,所以C 为钝角,所以该三角形为钝角三角形.故选择A.【点评】本题主要考查正弦定理及其推理、余弦定理的运用.主要抓住所给式子的结构来选择定理,如果出现了角度的正弦值就选择正弦定理,如果出现角度的余弦值就选择余弦定理.本题属于中档题.17.设443211010≤<<<≤x x x x ,5510=x ,随机变量1ξ取值54321x x x x x 、、、、的概率均为2.0,随机变量2ξ取值222221554433221x x x x x x x x x x +++++、、、、的概率也均为2.0,若记21ξξD D 、分别为21ξξ、的方差,则( ) A .21ξξD D > B .21ξξD D =C .21ξξD D < D .1ξD 与2ξD 的大小关系与4321x x x x 、、、的取值有关 【答案】 A【解析】 由随机变量21,ξξ的取值情况,它们的平均数分别为:1123451(),5x x x x x x =++++,2334455112211,522222x x x x x x x x x x x x +++++⎛⎫=++++= ⎪⎝⎭且随机变量21,ξξ的概率都为2.0,所以有1ξD >2ξD . 故选择A.【点评】本题主要考查离散型随机变量的期望和方差公式.记牢公式是解决此类问题的前提和基础,本题属于中档题. 18.设25sin1πn n a n =,n n a a a S +++= 21,在10021,,,S S S 中,正数的个数是( ) A .25 B .50 C .75 D .100 【答案】C【解析】依据正弦函数的周期性,可以找其中等于零或者小于零的项.【点评】本题主要考查正弦函数的图象和性质和间接法解题.解决此类问题主要找到规律,从题目出发可以看出来相邻的14项的和为0,这就是规律,考查综合分析问题和解决问题的能力.三、解答题(74分):19.(6+6=12分)如图,在四棱锥ABCD P -中,底面ABCD 是矩形,⊥PA 底面ABCD ,E 是PC 的中点,已知2=AB ,22=AD ,2=PA ,求:(1)三角形PCD 的面积;(2)异面直线BC 与AE 所成的角的大小. 【答案及解析】所以三角形PCD 的面积为3232221=⨯⨯................6分【点评】本题主要考查直线与直线、直线与平面的位置关系,考查空间想象能力和推理论证能力.综合考查空间中两条异面直线所成的角的求解,同时考查空间几何体的体积公式的运用.本题源于《必修2》立体几何章节复习题,复习时应注重课本,容易出现找错角的情况,要考虑全面,考查空间想象能力,属于中档题. 20.(6+8=14分)已知函数)1lg()(+=x x f . (1)若1)()21(0<--<x f x f ,求x 的取值范围;(2)若)(x g 是以2为周期的偶函数,且当10≤≤x 时,有)()(x f x g =,求函数)(x g y =(]2,1[∈x )的反函数.【答案及解析】,3132<<-x【点评】本题主要考查函数的概念、性质、分段函数等基础知识.考查数形结合思想,熟练掌握指数函数、对数函数、幂函数的图象与性质,属于中档题.21.(6+8=14分)海事救援船对一艘失事船进行定位:以失事船的当前位置为原点,以正北方向为y 轴正方向建立平面直角坐标系(以1海里为单位长度),则救援船恰好在失事船正南方向12海里A 处,如图.现假设:①失事船的移动路径可视为抛物线24912x y =;②定位后救援船即刻沿直线匀速前往救援;③救援船出发t 小时后,失事船所在位置的横坐标为t 7.(1)当5.0=t 时,写出失事船所在位置P 的纵坐标.若此时两船恰好会合,求 救援船速度的大小和方向;(2)问救援船的时速至少是多少海里才能追上失事船?22.(4+6+6=16分)在平面直角坐标系xOy 中,已知双曲线1C :1222=-y x . (1)过1C 的左顶点引1C 的一条渐进线的平行线,求该直线与另一条渐进线及x 轴围成的三角形的面积;(2)设斜率为1的直线l 交1C 于P 、Q 两点,若l 与圆122=+y x 相切,求证:OQ OP ⊥;(3)设椭圆2C :1422=+y x ,若M 、N 分别是1C 、2C 上的动点,且ON OM ⊥,求证:O 到直线MN 的距离是定值. 【答案及解析】过点A 与渐近线x y 2=平行的直线方程为, 1.y x y =+=+即1=ON ,22=OM ,则O 到直线MN .设O 到直线MN 的距离为d .【点评】本题主要考查双曲线的概念、标准方程、几何性质及其直线与双曲线的关系、椭圆的标准方程和圆的有关性质.特别要注意直线与双曲线的关系问题,在双曲线当中,最特殊的为等轴双曲线,它的离心率为2,它的渐近线为x y ±=,并且相互垂直,这些性质的运用可以大大节省解题时间,本题属于中档题 .23.(4+6+8=18分)对于数集}1{21n x x x X ,,,, -=,其中n x x x <<<< 210,2≥n ,定义向量集},),,(|{X t X s t s a a Y ∈∈==,若对任意Y a ∈1,存在Y a ∈2,使得021=⋅a a ,则称X 具有性质P .例如}2,1,1{-具有性质P . (1)若2>x ,且},2,1,1{x -具有性质P ,求x 的值;(2)若X 具有性质P ,求证:X ∈1,且当1>n x 时,11=x ;(3)若X 具有性质P ,且11=x 、q x =2(q 为常数),求有穷数列n x x x ,,, 21的通项公式.【答案及解析】必有形式),1(b -显然有2a 满足021=∙a a【点评】本题主要考查数集、集合的基本性质、元素与集合的关系等基础知识,本题属于信息给予题,通过定义“X具有性质P”这一概念,考查考生分析探究及推理论证的能力.综合考查集合的基本运算,集合问题一直是近几年的命题重点内容,应引起足够的重视.。
2013年高三物理教学质量检测试卷(第三次) 第I 卷(共56分)考生注意:满分150分。
考试时间120分钟。
请在答题纸上答题。
一.单项选择题(共16分,每小题2分.每小题只有一个正确选项)1.下列现象中,与原子核内部变化有关的是 (A )α粒子散射现象 (B )天然放射现象 (C )光电效应现象 (D )原子发光现象2.用单色光做单缝衍射实验,在屏幕上出现衍射条纹后,仅减小缝宽,则 (A )无法发生明显衍射现象 (B )中央明条纹宽度增加 (C ) 中央明条纹宽度减小 (D )中央明条纹宽度不变3.关于分子引力f 引和分子斥力f 斥与分子间距离r 的关系的说法中,正确的是 (A )当r 越小时,f 引越大,f 斥越小 (B )当r 越大时,f 引越大,f 斥越小 (C )无论r 多大,f 引总是小于f 斥 (D )当r 增大时,f 引和f 斥都会减小4.某学生在体育场上抛出铅球,不计阻力,其离手后运动轨迹如图所示。
则关于各点速度和加速度说法中正确的是 (A )v B >v C(B )v A >v D (C )各点加速度不同 (D )各点加速度相同5.如图,物体M 的各表面光滑,上表面水平,放在固定的斜面上。
在M 的水平上表面放一光滑小球m ,后释放M ,则小球在碰到斜面前的运动轨迹是(A )沿斜面向下的直线 (B )竖直向下的直线 (C )无规则的曲线 (D )抛物线6.如图所示,A 、B 分别表示某一个门电路两个输入端的信号,Z 表示该门电路输出端的信号,则根据它们的波形可以判断该门电路是(A )“与”门 (B )“或”门(C )“非”门 (D )“与非”门7.用等长的两根绳吊起一重物,使重物保持静止状态,如图所示。
设两根绳子的张力大小为T ,两个张力的合力为F ,当悬挂点A 、B 同时缓缓向左、右移开,使两根绳之间的夹角α渐渐增大,则 (A )T 逐渐增大,F 也逐渐增大 (B )T 逐渐增大,F 逐渐减小 (C )T 逐渐增大,F 大小不变 (D )T 逐渐减小,F 也逐渐减小8.从地面以大小为v 1的初速度竖直向上抛出一个皮球,经过时间t 皮球落回地面,落地时皮球速度的大小为v 2。
2012年向明中学高考模拟考数学试卷(理科)一. 填空题:(本题满分56分,每小题4分) 1.设集合21{|2},{1}2A x xB x x =-<<=≤,则A B = _______________.2.已知△ABC 中,3cot 4A =-,则cos A =_______________.3. 若数列{}n a 满足:111,2()n n a a a n N *+==∈,则前6项的和6S = . 4.设()()2,3,2,1a b ==- ,则a 在b上的投影为5.椭圆22192xy+=的焦点为12,F F ,点P 在椭圆上,若1||4PF =,则12F PF ∠的大小为_______________.6.函数()24(4)f x x x =-≥的反函数为________________.7.三阶行列式21145324---k 第2行第1列元素的代数余子式为10-,则=k____________.8.执行右边的框图:若输出的S 值满足811321<-<S ,则自然数p 的值为9.已知函数()200.618x f x x =⨯-的零点()0,1,x k k k ∈+∈Z ,则k = .10.某学生参加一次世博志愿者测试,已知在备选的10道试题中,预计每道题该学生答对的概率为23。
规定每位考生都从备选题中随机抽出3道题进行测试,则该学生仅答对2道题的概率是______________.(用数值表示)11.在极坐标系中,若过点(3,0)且与极轴垂直的直线交曲线4cos ρθ=于A 、B 两点,则A B =______________________.12.某班从5名班干部(其中男生3人,女生2人)中选3人参加学校学生会的干部竞选.设所选3人中女生人数为ξ,则随机变量ξ的方差=ξD ___________.13.A B C ∆中,已知2A B =,22AC =,则A C B ∠的最大值为_______________ . 14.已知集合M 是满足下列两个条件的函数)(x f 的全体:①)(x f 在定义域上是单调函数;开始 结束 输入p输出S n =0 , S=0n =n +1n < p nS S 21+=是 否②在)(x f 的定义域内存在闭区间],[b a ,使)(x f 在],[b a 上的值域为⎥⎦⎤⎢⎣⎡2,2b a .若函数m x x g +-=1)(,M x g ∈)(,则实数m 的取值范围是________________.二.选择题:(本题满分20分,每小题5分) 15. 复数31i i--等于---------------------------------------------------------------------------------( )A .i 21+ B.12i - C.2i - D.2i + 16.下列函数中,与函数1y x=有相同定义域的是--------------------------------------( )A .2()log f x x = B.1()f x x=C. ()||f x x =D.()2x f x =17.设P 是△ABC 所在平面内的一点,2BC BA BP +=,则----------------------------( )A. 0PA PB +=B. 0PB PC +=C. 0PC PA +=D. 0PA PB PC ++=18. 已知,AC BD 为圆22:4O x y +=的两条互相垂直的弦,,AC BD 交于点()1,2M ,则四边形A B C D 面积的最大值为----------------------------------------------------------------( ) A 4 B 5 C 6 D 7 三. 解答题:(本大题共5题,满分74分)19.(本题满分12分)本题共有2个小题,第1小题满分6分,第2小题满分6分.已知函数()2sin 2cos 6f x x x π⎛⎫=+- ⎪⎝⎭, ,2x ππ⎡⎤∈⎢⎥⎣⎦. (1)若54sin =x ,求函数)(x f 的值;(2)求函数)(x f 的值域.20.(本题14分,其中第(1)小题7分,第(2)小题7分)设在直三棱柱111A B C A B C -中,12A B A C A A ===,90BAC ∠=,,E F 依次为1,C C B C 的中点.(1)求异面直线1A B 、E F 所成角θ的大小(用反三角函数值表示); (2)求点1B 到平面AEF 的距离.21.(本小题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.ABCP第17题图某学校要建造一个面积为10000平方米的运动场。
福建省福州市第四十一中学初中英语教师教学论文 初三英语总复习教学中的几个变化 今年初三总复习教学即将结束,反思这届初三英语总复习教学,自己在教学上与往年的总复习教学进行了几个改变,并取得了较好的效果。
从教师提供详细的复习材料变为学生自行完成复习导纲。
过去,我总是将每课的词形变化、词组、句型以及语法等内容,全部打印成复习提纲,那么学生只是在上课时将这些复习提纲读一遍,然后回去背诵。
这种复习方法,没有给学生动脑的机会,只是将他们作为记忆的机器。
这种情况下,老师花了大量的时间、精力去归纳、打印提纲,但取得的效果并不理想。
今年,我将答案去掉,学生拿到的只是一份复习导纲。
那么学生就不得不翻开书,去查找解决的方法。
这样学生就主动动脑去思考,对复习的内容印象也更深。
从面面俱到变为重难点突出。
以往总复习过程中,总担心因为复习的不够详细,导致学生知识点没掌握,因此在语法讲解中,总是尽量详细、具体。
实际上,由于老师提供了太多的材料,以至于学生反而抓不住知识的重点。
这也体现了我对《大纲》没有吃透。
在本次总复习中,我紧紧抓住最重要的知识点,进行点拨,使学生对英语知识的结构了解得更清晰,对重难点的掌握更明确。
从课后练习到当场巩固。
往年总复习课,我总是在课堂上,不断地讲解知识点,学生单纯地记忆。
课后作业则是完成大量的练习,老师再进行讲评。
这样造成的问题是在题海中,学生把握不到练习的考点是什么,通过练习巩固知识的作用不明显。
在今年的总复习中,我通常是讲完几个知识点,马上进行小题量的巩固练习,并让学生分析题目的考点是什么。
这样学生完成了输入-内化-输出的过程。
练习从多而杂到精而少。
过去学生课堂复习后,往往要完成一份老师发的练习,而这份练习通常是现成的练习册或是一份试卷。
学生每天花大量的时间来完成书面练习。
今年,我根据中考题型以及每课的重难点,出一份精选的练习,题量少,但目的明确,使每道题都能体现一个知识点,不做单纯的重复练习。
2011学年嘉定区高三年级第三次模拟考试数学试卷(文科)(2012年5月14日)题号一二 三总分1—14 15—18 19 20 21 22 23得 分考生注意:本试卷共23题,满分150分,考试时间120分钟.一.填空题(本大题满分56分)本大题共有14题,只要求直接填写结果,每个空格填对得4分,否则一律得零分.1.设集合},1{R x x x A ∈<=,},4{2R x x x B ∈<=,则=B A ___________.2.设a 、R b ∈,i 为虚数单位,若i b i i a +=+)(,则复数bi a z +=的模为______. 3.函数x x y 2sin cos 2-=的最小正周期为_____________. 4.函数1)(-=x x f (1≥x )的反函数=-)(1x f _____________.5.系数矩阵为⎪⎪⎭⎫ ⎝⎛2312,解为⎪⎪⎭⎫⎝⎛=⎪⎪⎭⎫ ⎝⎛21y x 的一个线性方程组是_______________.6.已知向量)1,1(-=k a,)2,(-=k b ,若b a ⊥,则实数k 的值为_____________.7.若一个圆锥的主视图是边长为3的等边三角形,则该圆锥的侧面积是_____________.8.若a ,b ,c 成等比数列,则函数c bx ax x f ++=2)(的图像与x 轴交点的个数为_______. 9.设⎩⎨⎧<+-≥--=.0,42,0,12)(2x x x x x x f 则不等式2)(>x f 的解集为______________________.10.执行如下图所示的程序框图,那么输出的S 值为_____________.开始 1←k 0←S 50≤k k S S 2+← 1+←k k输出S结束是 否11.已知动圆圆心在抛物线x y 42=上,且动圆恒与直线1-=x 相切,则此动圆必过定点________________.12.从5名男生和2名女生中选出3人参加交通安全志愿者活动,则选出的3人中既有男生又有女生的概率是____________.13.实数x 、y 满足⎪⎩⎪⎨⎧≤+-≤≥,,12,1m y x x y y 如果目标函数y x z -=的最小值为1-,则实数m 的值为_________________.14.已知函数11)(+=x x f ,点n A 为函数)(x f 图像上横坐标为n (*N n ∈)的点,O 为坐标原点,向量)0,1(=e.记n θ为向量n OA 与e 的夹角,则=+++∞→)t a n t a n (t a n lim 21n n θθθ ___________.二.选择题(本大题满分20分)本大题共有4题,每题都给出代号为A 、B 、C 、D 的四个结论,其中有且仅有一个结论是正确的,必须把正确结论的代号写在题后的圆括号内,选对得5分,不选、选错或者选出的代号超过一个(不论是否都写在圆括号内),一律得零分. 15.“1tan =α”是“)(42Z k k ∈+=ππα”的…………………………………………( )A .充分非必要条件B .必要非充分条件C .充分必要条件D .既非充分又非必要条件 16.下列命题中正确的是……………………………………………………………………( )A .若bc ac >,则b a >B .若22b a >,则b a >C .若b a >,则b a >D .若ba 11<,则b a > 17.如图,四棱锥ABCD P -的底面是︒=∠60BAD 的菱形,且PC PA =,BD PB =,则该四棱锥的主视图(主视图投影平面与平面PAC 平行)可能是…………………( )A .B .C .D .18.若对于任意实数m ,关于x 的方程0)12(log 22=-++m x ax 恒有解,则实数a 的取值范围是……………………………………………………………………………………( )A .)1,(-∞B .]1,0(C .]1,0[D .)1,0(C ABDP三.解答题(本大题满分74分)本大题共有5题,解答下列各题必须写出必要的步骤. 19.(本题满分12分)本题共有2个小题,第1小题满分5分,第2小题满分7分.如图,在正三棱柱111C B A ABC -中,2=AB ,41=AA . (1)求三棱柱111C B A ABC -的表面积S ;(2)设E 为棱1BB 的中点,求异面直线E A 1与BC 所成角的 大小(结果用反三角函数值表示). 解:(1)(2) 20.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.如图,在平面直角坐标系xOy 中,M 、N 分别是椭圆12422=+y x 的顶点.过坐标原点的直线交椭圆于A 、B 两点,其中A 在第一象限.过点A 作x 轴的垂线,垂足为C .设直线AB 的斜率为k .(1)若直线AB 平分线段MN ,求k 的值; (2)当2=k 时,求点A 到直线BC 的距离. 解:(1)O ABCMNxyEC BA A 1B 1C 1(2) 21.(本题满分14分)本题共有2个小题,第1小题满分6分,第2小题满分8分.如图,角θ的始边OA 落在x 轴上,其始边、终边分别与单位圆交于点A 、C (20πθ<<),△AOB 为等边三角形.(1)若点C 的坐标为⎪⎭⎫⎝⎛53,54,求BOC ∠cos 的值; (2)设2||)(BC f =θ,求函数)(θf 的解析式和值域.解:(1)(2)OxyA BC小题满分6分.设向量)2,(x a = ,)12,(-+=x n x b (*N n ∈),函数b a y⋅=在]1,0[∈x 上的最小值与最大值的和为n a ,又数列}{n b 满足11=b ,121109-⎪⎭⎫⎝⎛=+++n n b b b .(1)求证:1+=n a n ;(2)求数列}{n b 的通项公式; (3)设n n n b a c ⋅-=,试问数列}{n c 中,是否存在正整数k ,使得对于任意的正整数n ,都有k n c c ≤成立?若存在,求出所有满足条件的k 的值;若不存在,请说明理由.解:(1)(2)(3)小题满分7分.已知函数b xax x f ++=)((0≠x ),其中a 、b 为实常数. (1)若方程13)(+=x x f 有且仅有一个实数解2=x ,求a 、b 的值;(2)设0>a ,),0(∞+∈x ,写出)(x f 的单调区间,并对单调递增区间用函数单调性定义进行证明;(3)若对任意的⎥⎦⎤⎢⎣⎡∈2,21a ,不等式10)(≤x f 在⎥⎦⎤⎢⎣⎡∈1,41x 上恒成立,求实数b 的取值范围. 解:(1)(2)(3)2011学年嘉定区高三年级第三次模拟考试数学试卷(文科)参考答案与评分标准一.填空题(每小题4分,满分56分)1.}12{<<-x x ;2.2;3.π;4.12+x (0≥x );5.⎩⎨⎧=+=+.723,42y x y x ; 6.1-或2;7.29π;8.0;9.),3()0,(∞+-∞ ;10.2550;11.)0,1(;12.75;13.5;14.1.二.选择题(每小题5分,满分20分) 15.B ;16.C ;17.B ;18.C .三.解答题 19.(第1小题5分,第2小题7分,满分12分) (1)32432=⋅=∆ABC S ,……(1分) 2446=⨯=侧S . ……(3分) 所以侧S S S ABC +=∆22432+=. ……(5分) (2)取1CC 中点F ,连结EF 、F A 1.因为EF ∥BC ,所以EF A 1∠就是异面直线E A 1与BC 所成角(或其补角).……(7分)在△EF A 1中,2=EF ,2211==F A E A ,42cos 1=∠EF A .…………(11分) 所以异面直线E A 1与BC 所成角的大小为42arccos.…………(12分) 20.(第1小题6分,第2小题8分,满分14分) (1)由题设知,2=a ,2=b ,故)0,2(-M ,)2,0(-N ,所以线段MN 中点的坐标为⎪⎪⎭⎫⎝⎛--22,1.………………(3分) 由于直线AB 平分线段MN ,故直线AB 过线段MN 的中点,又直线AB 过坐标原点,所以22122=--=k .…………(6分) FE CBAA 1B 1C 1(2)当2=k 时,直线AB 的方程为x y 2=,由⎪⎩⎪⎨⎧=+=,124,222y x x y 解得32±=x ,…(8分) 从而A 点的坐标是⎪⎭⎫ ⎝⎛34,32,B 点的坐标为⎪⎭⎫ ⎝⎛--34,32,……(10分)于是C 点的坐标为⎪⎭⎫⎝⎛0,32.…(11分)所以直线BC 的方程为032=--y x .…(12分)所以点A 到直线BC 的距离为3222343432=--=d .…………(14分)21.(第1小题6分,第2小题8分,满分14分) (1)由题意,3πθ+=∠BOC ,因为点C 的坐标为⎪⎭⎫⎝⎛53,54, 所以53sin =θ,54cos =θ,…………(3分) 所以10334235321543cos cos -=⋅-⋅=⎪⎭⎫⎝⎛+=∠πθBOC .…………(6分) (2)解法一:在△BOC 中,由余弦定理,BOC OC OB OC OB BC ∠-+=cos ||||2||||||222,……(7分) 所以⎪⎭⎫ ⎝⎛+-=3cos 22)(πθθf .…………(10分)因为20πθ<<,所以⎪⎭⎫⎝⎛∈+65,33πππθ,……(11分)所以)32,1()(+∈θf .…………(13分)因此,函数⎪⎭⎫ ⎝⎛+-=3cos 22)(πθθf (20πθ<<),)(θf 的值域是)32,1(+.(14分)解法二:由题意,⎪⎪⎭⎫⎝⎛-23,21B ,)sin ,(cos θθC ,……(7分) 所以⎪⎭⎫ ⎝⎛-+=-+=⎪⎪⎭⎫ ⎝⎛++⎪⎭⎫ ⎝⎛-=6s 22)c s 3(223s 21c o||222πθθθθθBC ……………………………………(10分)因为20πθ<<,所以⎪⎭⎫⎝⎛-∈-3,66πππθ,…(11分) 所以)32,1()(+∈θf .(13分) 所以,函数⎪⎭⎫ ⎝⎛++=6sin 22)(πθθf (20πθ<<),)(θf 的值域是)32,1(+.(14分)22.(第1小题4分,第2小题6分,第3小题6分,满分16分) (1)由已知,2)4()12(2)(2-++=-++=x n x x n x x y ……(2分) 而函数y 在]1,0[∈x 上是增函数,……(3分) 所以12412+=-+++-=n n a n .……(4分)(2)因为121109-⎪⎭⎫ ⎝⎛=+++n n b b b ,所以2121109--⎪⎭⎫ ⎝⎛=+++n n b b b (2≥n ),………………(6分)两式相减,得2109101-⎪⎭⎫⎝⎛⋅-=n n b ()2≥n .…………(8分)所以,数列}{n b 的通项公式为⎪⎩⎪⎨⎧⎪⎭⎫ ⎝⎛⋅-==-.109101,1,12n n n b …………(10分)(3)因为02111<-=-=b a c ,01091012>⎪⎭⎫⎝⎛⋅+=-n n n c (2≥n ),……(12分) 由题意,k c 为}{n c 的最大项,则2≥k ,要使k c 为最大值,则⎩⎨⎧≥≥+-,,11k kk k c c c c ……(13分)即⎪⎪⎩⎪⎪⎨⎧⎪⎭⎫ ⎝⎛⋅+≥⎪⎭⎫⎝⎛⋅+⎪⎭⎫ ⎝⎛⋅≥⎪⎭⎫ ⎝⎛⋅+----123210910210910110910109101k k k k k k k k ……(14分)解得9=k 或8=k . …………(15分)所以存在8=k 或9,使得k n c c ≤对所有*N n ∈成立.…………(16分) 23.(第1小题5分,第2小题6分,第3小题7分,满分18分) (1)由已知,方程13+=++x b xax 有且仅有一个解2=x , 因为0≠x ,故原方程可化为0)1(22=--+a x b x ,…………(1分)所以⎩⎨⎧=+-=--08)1(02102a b b a ,…………(3分)解得8-=a ,9=b .……(5分)(2)当0>a ,0>x 时,)(x f 在区间),0(a 上是减函数,在),(∞+a 上是增函数.…………(7分)(每个区间1分)证明:设),(,21∞+∈a x x ,且21x x <,112212)()(x ax x a x x f x f --+=-212112)(x x a x x x x -⋅-=, 因为),(,21∞+∈a x x ,且21x x <,所以012>-x x ,a x x >21,即a x x >21, 所以0)()(12>-x f x f .………………(10分) 所以)(x f 在),(∞+a 上是增函数.…………(11分) (3)因为10)(≤x f ,故⎥⎦⎤⎢⎣⎡∈1,41x 时有10)(max ≤x f ,……(12分) 由(2),知)(x f 在区间⎥⎦⎤⎢⎣⎡1,41的最大值为⎪⎭⎫⎝⎛41f 与)1(f 中的较大者.……(13分) 所以,对于任意的⎥⎦⎤⎢⎣⎡∈2,21a ,不等式10)(≤x f 在⎥⎦⎤⎢⎣⎡∈1,41x 上恒成立,当且仅当 ⎪⎩⎪⎨⎧≤≤⎪⎭⎫ ⎝⎛10)1(1041f f ,即⎪⎩⎪⎨⎧-≤-≤a b a b 94439对任意的⎥⎦⎤⎢⎣⎡∈2,21a 成立.…………(15分) 从而得到47≤b . …………(17分) 所以满足条件的b 的取值范围是⎥⎦⎤⎝⎛∞-47,. …………(18分)。
上海市嘉定区2011—2012学年度高三第三次质量调研英语试题(120分钟完成; 总分:150分)第I卷(共105 分)I. Listening ComprehensionSection ADirections: In Section A, you will hear ten short conversations between two speakers. At the end of each conversation, a question will be asked about what was said. The conversations and the questions will be spoken only once. After you hear a conversation and the question about it, read the four possible answers on your paper, and decide which one is the best answer to the question you have heard.1. A. At home. B. On the farm. C. In a restaurant. D. In a supermarket.2. A. $6. B. $4.5. C. $5. D. $4.3. A. A worker at McDonald’s. B. A student.C. A tutor.D. A salesman in a market.4. A. She didn’t receive the E-mail. B. She is too busy to check the E-mail.C. Her computer broke down.D. She has replied to his E-mail.5. A. It’s certain that they will come to the lecture.B. They won’t come if they don’t call first.C. She is worried about it.D. There are plenty of seats for all the people.6. A. She wishes the teacher could talk more.B. She thinks the teacher has an accent.C. She didn’t always catch the teacher.D. She thinks the teacher should talk louder.7. A. She will pick up Jack at 2:00 in the afternoon.B. She won’t be able to meet Jack at the airport.C. She doesn’t want to meet Jack at the airport.D. She doesn’t know when Jack will arrive.8. A. She is looking for a job in the summer.B. She is eager to go home for the vacation.C. She doesn’t know where to go in summer.D. She doesn’t want to go home in summer.9. A. The woman goes to work by bike every day.B. The woman used to go to work by bike.C. The woman has bought a new bike.D. The man’s bike was stolen.10. A. The man wants to help the woman to find the lunch box.B. The man doesn’t know what to do.C. The man will buy lunch for the woman.D. The man will give the woman a treatment.Section BDirections:In Section B, you will hear two short passages, and you will be asked three questions on each of the passages. The passages will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers on your paper and decide which one would be the best answer to the question you have heard.Questions 11 through 13 are based on the following passage.11. A. Keep a high level of care for the people. B. Pay for damage done by dogs.C. Provide medical care for dogs.D. Buy insurance for dog owners.12. A. The owner of the car. B. The owner of the dog.C. The insurance company.D. The government.13. A. Dogs are welcome in public places. B. Keeping dogs means asking for trouble.C. Many car accidents are caused by dogs.D. People care much about dogs.Questions 14 through 16 are based on the following passage.14. A. Information research. B. Research for advertising.C. Market research.D. Research for media.15. A. Consumers and their occupation. B. Consumers and their buying habits.C. Consumers and their behavior.D. Consumers and their automobiles.16. A. Why people purchase certain products. B. Who will probably buy certain products.C. How the ad can best show the products.D. Where the ad can be best displayed.Section CDirections:In Section C, you will hear two longer conversations. The conversations will be read twice. After you hear each conversation, you are required to fill in the numbered blanks with the information you have heard. Write your answers on your answer sheet.Complete the form. Write ONE WORD for each answer.Listening:Ⅱ. Grammar and VocabularySection ADirections: Beneath each of the following sentences there are four choices marked A, B, C and D. Choose the one answer that best completes the sentence.25. Many young people took ______ the work the minute they started their voluntary service atthe World Expo site.A. upB. toC. afterD. off26. They first met each other ten years ago and they ______ good friends ever since.A. had beenB. have madeC. had madeD. have remained27. A terrible bus accident happened on April, 22, 2012 somewhere near Changshu, JiangsuProvince, ______14 passengers killed and 21 injured.A. leftB. leavingC. to leaveD. having left28. I simply cannot forget Mr. Smith, ______ idea was the most instructive for my initial design.A. of whichB. whichC. whoseD. of whom29. Though both born and brought up in Shanghai, ______ of the two brothers knows the citymuch better.A. the elderB. the oldestC. the oldD. the eldest30. The ongoing global financial crisis will go from bad to worse ______ more attention is paid tothe real economy.A. in case thatB. onceC. provided thatD. unless31. Lili was so nervous that not a single word down in the dictation.A.she wrote B.she was written C.did she write D.was she written32. Fast food such as KFC may owe their popularity to the fact that there is usually little _____.A. to wait forB. waitingC. to be waited forD. waited33. She ______ called to say sorry to me, but my mobile phone was power-off all day long.A. needn’t haveB. should haveC. could haveD. mustn’t have34. ____ three times in a row, the boxer decided to give up fighting.A. Having defeatedB. To have defeatedC. Having been defeatedD. To have been defeated35. I’d like to see my children try their best to do everything rather than get them ______.A. spoiledB. to spoilC. spoilingD. to be spoiled36. As is reported,women with demanding jobs are almost to suffer a heart attack.A. twice likely asB. as likely twiceC. likely twice asD. twice as likely37. —I don’t suppose our coach knows the real reason for our losing the match.—Well, surprisingly, he does. Our team leader has been called in and now.A.has been questioned B.is being questionedC.is questioning D.has questioned38. Tea ceremony, though it is now most popular in Japan, is said ______ in ancient China.A. to have originatedB. to have been originatedC. to be originatingD. to have been originating39. A conclusion was reached at the meeting ______ education must cater to individual interest.A. whichB. howC. thatD. where40. Mary has just purchased herself_____ dress.A. an expensive blue cottonB. a cotton blue expensiveC. a blue expensive cottonD. a cotton expensive blue.Section BDirections: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.A new study found that inner-city kids living in neighborhoods with more green space gained about 13% less weight over a two-year period than kids living among more concrete and fewer trees. Such 41 tell a powerful story. The obesity epidemic (肥胖病)began in the 1980s, and many people hold the view that the improper diet and lack of activity contribute to the disease, but that can’t be everything. Fast foods and TVs have been with us for a long time. “Most experts agree that the changes were 42 to something in the environment,”says social epidemiologist Thomas Glass of The Johns Hopkins Bloomberg School of Public Health. That something could be a shrinking of the green.The new research, published in the American Journal of Preventive medicine, isn’t the first to associate greenery with better health, but it does get us closer to 43 what works and why. It’s clear that a green neighborhood means more places for kids to play—which is vital since time spent outdoors is one of the strongest connection of children’s activity levels. But green space is good for the mind too: research by environmental psychologists has shown that it has mental 44 for children with attention-deficit disorder (注意力缺乏症). In one study, just reading outside in a green setting improved kids’symptoms. The study indicates that 45 to grassy areas has also been linked to less stress and a lower body mass index(体重指数) among adults. And an 46 of 3,000 Tokyo residents associated green spaces with greater long life among senior citizens.However, Thomas Glass points out that most studies don’t 47 prove a causal link between greenness and health, but they’re helping stimulate action. In September the U.S. House of Representatives 48 a proposal, the delightfully named No Child Left Inside Act to encourage public projects aimed at exposing kids to the outdoors.Finding green space is not always easy, and you may have to work a bit to get your family a little grass and trees. If you live in the countryside or a city with good parks, take advantage of what’s there. Your children in particular will love it—and their bodies and minds will be 49to you.III. Reading ComprehensionSection ADirections: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.From childhood to old age, we all use language as a means of broadening our knowledge of ourselves and the world about us. When humans first 50 , they were like newborn children, unable to use this 51 tool. Yet once language developed, the possibilities for human kind’s future achievements and cultural growth increased.Many language experts believe that evolution is 52 for our ability to produce and use language. They 53 that our highly evolved brain provides us with an innate (inborn:天生的) language ability not found in lower organisms (生物,有机体). Those who support this innateness theory say that our 54 for language is inborn, but that language develops gradually, as a function of the growth of the brain during childhood. Therefore there are critical 55 time for language development.Current 56 of innateness theory are mixed; however, evidence supporting the existence of some innate abilities can not be denied. 57 , more and more schools (流派) are discovering that foreign languages are best taught in 58 grades. Young children often can learn several languages by being 59 to them, while adults have a much harder time learning another language once the 60 of their first language have become firmly fixed.61 some aspects of language are innate, language does not develop automatically of itself. Children who have been 62 from other human beings do not possess language. This demonstrates that interaction or communication with other human beings is necessary for proper language development. Some language experts believe that this is even more basic to human language acquisition(习得) than any innate abilities. These theorists view language as imitative, learned behavior. 63 , children learn language from their parents by imitating them. Parents gradually shape their child's language skills by giving 64 feedback to precise imitations and negative feedback to imprecise ones.50. A. produced B. evolved C. born D. originated51. A. valuable B. appropriate C. convenient D. favorite52. A. permanent B. available C. reliable D. responsible53. A. assure B. inform C. claim D. convince54. A. potential B. performance C. preference D. passion55. A. personal B. biological C. social D. psychological56. A. reviews B. reference C. reaction D. recommendation57. A. In a word B. In a sense C. In fact D. In other words58. A. various B. different C. the higher D. the lower59. A. revealed B. exposed C. engaged D. involved60. A. requirements B. formations C. rules D. construction61. A. Although B. Whether C. Since D. When62. A. distinguished B. different C. protected D. isolated63. A. As a result B. After all C. In other words D. Above all64. A. inspiring B. positive C. satisfying D. exactSection BDirections:Read the following three passages. Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A, B, C and D. Choose theone that fits best according to the information given in the passage you have just read.AA new study of 8,000 young people in the Journal of Health and Social Behavior shows that although love can make adults live healthily and happily, it is a bad thing for young people. Puppy love(早恋)may bring stress for young people and can lead to depression. The study shows that girls become more depressed than boys, and younger girls are the worst of all.The possible reason for the connection between love and higher risk of depression for girls is “loss of self”. According to the study,even though boys would say “lose themselv es in a romantic relationship”, this “loss of self” is much more likely to lead to depression when it happens to girls. Young girls who have romantic relationships usually like hiding their feelings and opinions. They won’t tell that to their parents.Dr Marianm Kaufman,an expert on young people problems, says 15% to 20% young people will have depression during their growing. Trying romance often causes the depression. She advises kids not to jump into romance too early. During growing up, it is important for young people to build strong friendships and a strong sense of self. She also suggests the parents should encourage their kids to keep close to their friends,attend more interesting school activities and spend enough time with family.Parents should watch for signs of depression—eating or mood changes—and if they see signs from their daughters or sons, they need to give help. The good news is that the connection between romance and depression seems to become weak with age.Love will always make us feel young,but only maturity gives us a chance to avoid its bad side effects.65. What’s the main idea of the passage?A. Puppy love may bring young people depression.B. Parents should forbid their children’s love.C. Romance is a two-edged sword for adults.D. Romance is good for young people.66. Which of the following is more likely to have depression?A. Young people who have a strong sense of selfishness.B. Young boys whose parents watch for their behavior.C. Young girls who always hide their feelings and opinions.D. Careless parents whose children are deep in love.67. What can be inferred from the passage?A. Lacking love can lead young people to grow up more quickly.B. Early love makes young people keep close to their friends and parents.C. Parents should help their children to be aware of the signs of depression.D. The older a woman is, the less likely she seems to lose herself in romance.68. What’s the author’s attitude towards puppy love?A. ConfusedB. DisapprovingC. UninterestedD. ScaredB69. A boy who likes writing poems can attend an event on _______.A. January 2B. January 3 3C. February 20D. March 170. Who would be most likely to attend the event held on Wednesday, January 9, 2012?A. A science teacher.B. A retired worker.C. A school headmaster.D. A supermarket owner.71. Which event doesn’t need booking in advance?A. One-on-One Computer or Internet Training Session.B. Beyond Journal Writing for Teens.C. Power Panels and Films by World Savvy.D. Business Counseling Sessions.CGroup buying is one of the fastest growing trends in South Africa today. Industry leaders are confident the growth potential remains strong since group buying is location-specific(区域性的). Start-up costs are low and profit room remains high, so many sites continue to receive invested money despite widespread criticism and Facebook’s decision to phase out of the deals business due to privacy concerns.In the early stages of all industries, some companies fail because they cannot compete with stronger companies in difficult economic conditions. To deal with difficult conditions, an alarming number of businesses are developing group buying websites in places like China and India, so the increase of group buying in South Africa is nothing more than a natural progression into theinternational mainstream.The group buying concept is fairly new and consumers have accepted this concept because they can now make full use of the rich information available on the Internet. Group buying is convenient and easy so it works. Anyone can view a site, join a mailing list, subscribe to RSS or print out a coupon(优惠券). The current group buying structure offered by the industry leaders works although there are still challenges to overcome.Perhaps, the future of group buying is tied to the joining together of social media and mobile devices. Mobile devices are with us wherever we go and almost everyone is using some type of social media site like Facebook or Twitter to stay informed. Using GPS and social media technology to provide real time location-specific promotions would be beneficial to every consumer looking for the best deals in town.Pause for a moment and think about it! What is better than signing on to your phone while having fun in town and you receive a real time information that your favorite shop across the street is offering a killer deal?The future of the group buying in South Africa is bright and we can expect to see more advanced approaches to this concept in the future. In addition to the technological advances consumers will see the range of promotions expand to include new products and services.72. What does the underlined phrase “pha se out of” mean in the passage?A. Gradually stop.B. Gradually increase.C. Begin to develop.D. Continue to enlarge.73. The author sets China and India as examples to show that _________.A. China and India are powerful countriesB. China and India are in difficult economic conditionsC. group buying is successful worldwideD. group buying is an international trend74. Which of the following is true according to the passage?A. People have accepted group buying because it’s a new concept.B. Social media and mobile devices have been joined together for group buying.C. GPS and social media technology will be helpful in group buying.D. Shops usually offer a killer deal when their customers are having fun.75. The author’s attitude towards the futu re of group buying is __________.A. pessimisticB. optimisticC. objectiveD. subjectiveSection CDirections:Read the following text and choose the most suitable heading from A-F for eachThe earth is getting warmer. People burn coal, oil and gas and this produces carbon dioxide,methane and nitrous oxide. These gases, called “greenhouse gases”, prevent the heat of the sun from leaving the earth’s upper atmosphere and this makes the earth warmer.A few weeks ago a group of scientists produced a report about global warming and the natural world. They wanted to find out if global warming was dangerous for plants and animals. According to what they found, the scientists say that during the next 50 years about 25% of land animals and plants will become extinct. More than a million plant and animal species will be extinct by 2050.More than 10% of all plants and animals will become extinct. It is too late to save many plants and animals because of the greenhouse gases that are already in the atmosphere. But the scientists say if we control greenhouse gases now, we could save many more plants and animals from extinction.The scientists studied some regions of the world with a very rich biology. These regions were Europe, Australia, Central and South America, and South Africa. Their studies showed that species living in mountainous areas had a better chance of survival because they could move uphill, to get cooler. In flat areas, such as deserts, plants and animals would have to move a very long distance to get cooler, so they are in greater danger of extinction.The scientists found that half of the 24 species of butterflies they studied in Australia would soon become extinct. 60% of the species in the Kruger National Park in South Africa would also die out, and more than 100% of the 300 South Africa plant species they studied would also become extinct. One of the plants in danger of extinction is the national flower of South Africa, the King Protea. They studied 163 tree species in the Cerrado region of Brazil and found that 70 would become extinct. Many of the plants and trees that live in this region live nowhere else in the world. In Mexico, they studied 1,870 species and found that more than 30% of these were in danger of extinction.Section DDirections:Read the passage carefully. Then answer the questions or complete the statements in the fewest possible words.Job sharing refers to the situation in which two people divide the responsibility of one full time job. The two people willingly act as part-time workers, enough hours between them to fulfill the duties of a full-time worker. If they each work half the job, for example, they each receive 50 percent of the job's wages, its holidays and its other benefits.Job sharing differs from conventional part-time work in that it occurs mainly in the more highly skilled and professional areas, which require higher levels of responsibility and employee commitment.Job sharing should not be confused with the term work sharing, which refers to increasing the number of jobs by reducing the number of hours of each existing job, thus offering more positions to the growing number of unemployed people. Job sharing, by contrast, is not designed to deal withunemployment problems; its focus, rather, is to provide well-paid work for skilled workers and professionals who want more free time for other activities.As would be expected, most job sharers are women. A survey carried out in 2010 by Britain’s Equal Opportunities Commission showed that 78 per cent of sharers were female, the majority of whom were, between 20 and 40 years of age. Subsequent studies have come up with similar results. Many of these women were reentering the job market after having had children, but they chose not to seek part –time work because it would have meant lower status. Job sharing also offered an acceptable shift back into full – time work after a long absence.The necessity of close cooperation when sharing a job with another person makes the actual work quite different from conventional one-position jobs. However, to ensure a greater chance that the partnership will succeed, each person needs to know the strengths, weaknesses and preferences of his or her partner before applying for a position. Moreover, there must be a fair division of both routine tasks and interesting ones. In sum, for a position to be job-shared well, the two individuals must be well matched and must treat each other as equals.(Note: Answer the questions or complete the statements in NO MORE THAN TEN WORDS.) 81.What is work sharing designed to do?______________________________________________________________________ 82.According to paragraph 4, why did young mothers prefer job sharing to conventional part – time work?______________________________________________________________________83.In job sharing the partners should ________________________________________. 84.The main purpose of the passage is to _____________________________________.第II卷(共45 分)I. TranslationDirections: Translate the following sentences into English, using the words given in the brackets.1、没有人能够容忍你举止粗鲁。
2012学年嘉定区高三年级第三次质量调研数学试卷(理)
参考答案与评分标准
一.填空题(每小题4分,满分56分) 1.i 2±; 2. 5; 3.}1,0{; 4.⎥⎦
⎤
⎢⎣
⎡+
+32,6
πππ
πk k (Z ∈k ); 5.2; 6.
π4或
π
8
; 7.1; 8.]4,26[-; 9.相交; 10.2;
11.)0(g ,)2(f ,)3(f ; 12.12; 13.x y 2±=; 14.4.
二.选择题(每小题5分,满分20分) 15.A ; 16.C ; 17.B ; 18.D .
三.解答题(本大题满分74分,注:评分标准中解答题的得分按各步给出,非递进累计分) 19.(1)以A 为原点,AB 、AD 、AP 所在直线为
x 轴、y 轴、z 轴建立空间直角坐标系.……(1分) 则)0,0,0(A ,)0,0,1(B ,)0,1,1(C ,)0,1,0(D , …………………………(1分) 设a PA =,则),0,0(a P ,
因为M 是PC 中点,所以⎪⎭
⎫
⎝⎛2,21,21a M ,……(1分) 所以⎪⎭
⎫
⎝⎛=2,21,21a ,)0,1,1(-=,),0,1(a -=.…………(1分) 因为⊥AM 平面PBD ,所以BD AM ⊥,BP AM ⊥,
所以02
212
=+-a ,解得1=a .………………………………(1分) 所以1=PA ,四棱锥ABCD P -的体积为3
1
. ……………(1分)
(2)⎪⎭
⎫
⎝⎛=21,21,21,)0,1,0(=,设平面AMD 的一个法向量为),,(z y x n = ,则⎩⎨
⎧==++,
0,0y z y x 1-=x ,可得)1,0,1(-=n
, ……………………(3分) 又)1,1,1(--=CP ,设CP 与n
的夹角为θ,则3
6
3
22|
|||c
o s =
⋅=
⋅=CP AM θ. ……………………(2分) 所以,直线PC 与平面AMD 所成角的大小为3
6
arcsin
. ………………(1分)
20.(1)由题意,32=A ,设函数x A y ωsin =在R 上的周期为T ,则34
=T
, 又ω
π
2=
T ,所以6
π
ω=
, ………………(2分)
所以x y 6
sin
32π
=,当4=x 时,3=y ,故)3,4(M ,…………(2分)
因为)0,8(P ,所以53)84(||22=+-=
MP .…………(1分)
即MP 的长为5千米. …………………………(1分)
(2)在△MNP 中,32π=
∠MNP ,θ=∠PMN ,则3
0π
θ<<,…………(1分) 由正弦定理得,⎪⎭
⎫ ⎝⎛-=
=θπθπ3sin |
|sin ||32sin ||MN NP MP , 所以θsin 3310||=
NP ,⎪⎭
⎫ ⎝⎛-=θπ3sin 3310||MN , …………(2分) 所以⎪⎪⎭
⎫ ⎝⎛+=+⎪⎭⎫ ⎝⎛-=+θθθθπcos 23sin 213310sin 33103sin 3310||||NP MN
⎪⎭⎫
⎝
⎛+=
3sin 3310πθ, ………………(3分) 因为30πθ<<,所以当6π
θ=时,折线段赛道MNP 最长. …………(2分)
21.(1)设等比数列}{n a 的公比为q ,等差数列}{n b 的公差为d .
由已知得,q a 32=,233q a =,d b 334+=,d b 12313+=,…………(1分) 所以,
⎩⎨⎧+=+=,1233,3332d q d q 即⎩⎨⎧+=+=,
41,
12
d q d q 解得3=q 或1=q (舍去),所以2=d .……(3分) 所以n n a 3=,12+=n b n . ……(2分)
(2)由题意得n n n n n n n a b c 3)12()1()1(++⋅-=+⋅-=,…………(1分) 所以,
)12()1()12()1()97()53(121+-+--+++-++-=+++=-n n c c c S n n n n )333(2n ++++ , ……………………(1分)
所以,当n 为偶数时,2
3
2331)31(31-+=--+
=+n n S n n n ; …………(3分) 当n 为奇数时,2
7
2331)31(3)12(11--=--+
+--=+n n n S n n n . …………(3分)
22.(1)解法一:设),(00y x C ,),(y x D ,则),2(00y x AC +=, ……(1分)
又)0,4(=,),2(y x +=⎪⎭⎫ ⎝⎛+=2,3200y x ,则⎩⎨
⎧=-=,2,220
0y y x x ……(1分) 代入4)2(||2
0202=++=y x ,得122=+y x , …………(1分)
即动点D 的轨迹方程为122=+y x . ……………………(1分)
解法二:设),(y x D ,由已知)2,2()0,4(),2(22y x y x AB AD AC =-+=-=,(2分) 由2||=AC 得44422=+y x , ……(1分)
即动点D 的轨迹方程为122=+y x .…………(1分)
(2)由题意,直线l 的斜率存在.设l 的方程为)2(+=x k y ,
设椭圆的方程为14
22
22=-+a y a x (2>a ),…………(1分)
由⎪⎩⎪⎨⎧=-++=,14,22
2
22a y a
x kx y 得0444)4(2422222222=+-++-+a a k a x k a x a k a .…(1分) 由l 与圆122=+y x 相切,得11
|
2|2=+k k ,312=k , …………(1分)
得04
34)3(4
2
2
2
2
=-
++-a a x a x a . 设),(11y x M ,),(22y x N ,则3
22
21--=+a a x x . ………………(1分)
又线段MN 中点到y 轴的距离5
4)3(222
221=-=+a a x x ,所以82
=a .…………(1分) 所以所求椭圆的方程为14
82
2=+y x . …………(1分) (3)由(2)知)2,0(G ,设直线m :2+=kx y ,代入椭圆方程得8)2(22
2=++kx x ,
即08)12(2
2
=++kx x k , ………………(1分)
解得⎪⎪⎭
⎫ ⎝⎛+-+-2
2
22142,218k k k k P . ………………(1分) 同理,直线n 的方程为21+-=x k y ,⎪⎪⎭⎫
⎝⎛+-+242,28222k k k k Q . …………(2分) 故直线PQ 的方程为⎪⎭
⎫ ⎝⎛++-=+--2222218312142k k x k k k k y , …………(2分)
令0=x ,得3
2
-=y . …………(1分)
所以,直线PQ 经过定点⎪⎭⎫ ⎝
⎛
-32,0. …………(1分)
23.(1)a b x a x g -++-=1)1()(2,
因为0>a ,所以)(x g 在区间]3,2[上是增函数,……(1分)
故⎩
⎨
⎧==,4)3(,
1)2(g g …………(2分)
解得1=a ,0=b . …………(1分)
(2)由(1)12)(2+-=x x x g ,故1||2)(2+-=x x x f 是偶函数,……(2分) 所以不等式)2()(log 2f k f >可化为2|log |2>k , …………(2分) 解得),4(41,
0∞+⎪⎭
⎫
⎝⎛
∈ k . ……………………(2分) (3)因为⎪⎩⎪⎨⎧<++≥+-=,
0,12,
0,12)(22x x x x x x x f 所以)(x f 为]3,1[上的单调递增函数,…(1分)
则对于任意满足311210=<<<<<=-n n x x x x x (*
N ∈n ,3≥n )的自变量0x ,1x ,
2x ,…,n x ,有)3()()()()()()1(1210f x f x f x f x f x f f n n =<<<<<=- ,
…………………………………………………………………………(2分)
所以,
)()()()(|)()(||)()(||)()(|120111201x f x f x f x f x f x f x f x f x f x f n n -+-=-++-+-- 4)1()3()(()()(01=-=-=-++-f f x f x f x f x f n n n , …………(3分)
所以存在常数4≥M ,使得
M x m x m x m x m x m x m n n ≤-++-+--|)()(||)()(||)()(|11201 . …………(1分)
函数)(x f 为区间]3,1[上的有界变差函数.即M 的最小值为4. ………………(1分)。