东北农业大学网络教育学院模拟题东农高起点数学.docx

注：装订线内禁止答题，装订线外禁止有姓名和其他标记。

东北农业大学网络教育学院在职高升专期末测试题23207127计算机应用基础一、单项选择题(每题1.5分，共40题)1. 以下操作系统中，不是多任务操作系统的是。

AA.MS-DOSB.Windows XPC.Windows 7D. Linux2. 在Excel中，被选定的单元格区域自动带有。

AA.黑色粗边框B.红色边框C.蓝色边框D.黄色粗边框3. 新购置的裸机首先要安装。

BA.字处理软件B.操作系统C.应用程序D.高级语言4. 在Word中可以为文本添加下划线的快捷键是。

BA.Ctrl + IB.Ctrl + UC.Ctrl + AD.Ctrl + B5. PowerPoint2010中，执行了插入新幻灯片的操作，被插入的幻灯片将出现在。

BA.当前幻灯片之前B.当前幻灯片之后C.最前D.最后6. Windows7中，为保护文件不被修改，可将它的属性设置为。

BA.存档B.只读C.隐藏D.系统7. 在PowerPoint2010中，幻灯片的放映方式主要有种。

BA.2B.3C.4D.58. 当保存演示文稿时“另存为”对话框，则说明。

CA.该文件不能保存B.该文件保存时不能用该文件原来的文件名C.该文件未保存过D.该文件已经保存过9. 关于PowerPoint2010以下说法正确的是。

BA.在PowerPoint2010不能把文件保存为xml格式B.在PowerPoint2010能把文件保存为xls格式C.在PowerPoint2010能把文件保存为jpg格式D.在PowerPoint2010中不能把文件保存为pdf格式10. Excel2010是。

CA.数据库管理软件B.文字处理软件C.电子表格软件D.幻灯片制作软件11. 在PowerPoint 2010中，通常用于为幻灯片添加注释说明。

CA.幻灯片窗格B.视图窗格C.备注窗格D.编辑窗格12. 关于筛选，叙述正确的是。

东北农业大学入学测试机考高起点数学模拟试题1、题目 B1-1 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C2、题目 B1-2 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D3、题目 B1-3 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C4、题目 B1-4 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D5、题目 B1-5 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A6、题目 B1-6 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C7、题目 B1-7 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C8、题目 B1-8 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C9、题目 B1-9 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B10、题目 D1-1〔 2〕〔〕A ． AB． BC． CD． D标准答案： B11、题目 B1-10 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C12、题目 D1-2〔 2〕〔〕A ． AB． BC． CD． D标准答案： B13、题目 B1-11 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C14、题目 D1-3〔 2〕〔〕A ． AB． BC． CD． D标准答案： C15、题目 D1-4〔 2〕〔〕A ． AB． BC． CD． D标准答案： D16、题目 D1-5〔 2〕〔〕A ． AB． BC． CD． D标准答案： C17、题目 D1-6〔 2〕〔〕A ． AB． BC． CD． D标准答案： C18、题目 D1-7〔 2〕〔〕A ． AB． BC． CD． D标准答案： C19、题目 D1-8〔 2〕〔〕A ． AB． BC． CD． D标准答案： C20、题目 D1-9〔 2〕〔〕A ． AB． BC． CD． D标准答案： B21、题目 D1-10 〔2〕〔〕A ． AB． BC． CD． D标准答案： B22、题目 D1-11 〔 2〕〔〕A ． AB． BC． CD． D标准答案： C23、题目 D1-12 〔2〕〔〕A ． AB． BC． CD． D标准答案： A24、题目 D1-13 〔2〕〔〕A ． AB． BC． CD． D标准答案： A25、题目 D1-14 〔2〕〔〕A ． AB． BC． CD． D标准答案： C26、题目 D1-15 〔2〕〔〕A ． AB． BC． CD． D标准答案： D27、题目 D1-16 〔2〕〔〕A ． AB． BC． CD． D标准答案： D28、题目 D1 －17〔 2〕〔〕A ． AB． BC． CD． D标准答案： D29、题目 D1-18 〔2〕〔〕A ． AB． BC． CD． D标准答案： A30、题目 B1-12 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： A31、题目 B1-13 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： B32、题目 B1-14 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： D33、题目 B1-15 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： A34、题目 B2-1 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C35、题目 B2-2 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A36、题目 B2-3 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A37、题目 B2-4 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C38、题目 B2-5 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B39、题目 B2-6 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A40、题目 B2-7 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C41、题目 B2-8 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C42、题目 B2-9 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A43、题目 B2-10 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： A44、题目 B2-11 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D45、题目 B2-12 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： D46、题目 B2-13 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： C47、题目 B2-14 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： B48、题目 B2-15 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： B49、题目 B3-1 ：〔 2〕〔〕A ． AB． BC． C标准答案： B50、题目 B3-2 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B51、题目 B3-3 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A52、题目 B3-4 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D53、题目 B3-5 ：〔 2〕〔〕A ． AC． CD． D标准答案： A54、题目 B3-6 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C55、题目 B3-7 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B56、题目 B3-8 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C57、题目 B3-9 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B58、题目 B3-10 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： A59、题目 B3-11 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C60、题目 B3-12 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： D61、题目 B3-13 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： D62、题目 B3-14 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： B63、题目 B3-15 ：〔2〕〔〕A ． AB． BC． CD． D标准答案： D64、题目 D3-6〔 2〕〔〕A ． AB． BC． CD． D标准答案： D65、题目 D3-7〔 2〕〔〕A ． AB． BC． CD． D标准答案： D66、题目 D3-8〔 2〕〔〕A ． AB． BC． CD． D标准答案： B67、题目 D3-9〔 2〕〔〕A ． AB． BC． CD． D标准答案： A68、题目 D3-10 〔2〕〔〕A ． AB． BC． CD． D标准答案： A69、题目 G1-1〔 2〕〔〕A ． AB． BC． CD． D标准答案： D70、题目 G1-2〔 2〕〔〕A ． AB． BC． CD． D标准答案： A71、题目 G1-3〔 2〕〔〕A ． AB． BC． CD． D标准答案： D72、题目 G1-4〔 2〕〔〕A ． AB． BC． CD． D标准答案： B73、题目 G1-5〔 2〕〔〕A ． AB． BC． CD． D标准答案： A74、题目 G1-6〔 2〕〔〕A ． AB． BC． CD． D标准答案： C75、题目 G1-7〔 2〕〔〕A ． AB． BC． CD． D标准答案： B76、题目 G1-8〔 2〕〔〕A ． AB． BC． CD． D标准答案： A77、题目 G1-9〔 2〕〔〕A ． AB． BC． CD． D标准答案： A78、题目 G1-10〔2〕〔〕A ． AB． BC． CD． D标准答案： B79、题目 G1-11〔 2〕〔〕A ． AB． BC． CD． D标准答案： B80、题目 G1-12〔2〕〔〕A ． AB． BC． CD． D标准答案： C81、题目 G1-13〔2〕〔〕A ． AB． BC． CD． D标准答案： A82、题目 G1-14〔2〕〔〕A ． AB． BC． CD． D标准答案： C83、题目 G1-15〔2〕〔〕A ． AB． BD． D标准答案： D84、题目 G1-16〔2〕〔〕A ． AB． BC． CD． D标准答案： D85、题目 G1-17〔2〕〔〕A ． AB． BC． CD． D标准答案： D86、题目 G1-18〔2〕〔〕A ． AB． BC． CD． D标准答案： A87、题目 G1-19〔2〕〔〕A ． AB． BD． D标准答案： C88、题目 W1-1 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D89、题目 W1-2 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： A90、题目 W1-3 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B91、题目 W1-4 ：〔 2〕〔〕B． BC． CD． D标准答案： C92、题目 W1-5 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D93、题目 W1-6 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C94、题目 W1-7 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C95、题目 W1-8 〔 2〕〔〕B． BC． CD． D标准答案： C96、题目 W1-9 〔 2〕〔〕A ． AB． BC． CD． D标准答案： A97、题目 W1-10 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C98、题目 W1-11 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： C99、题目 W1-12 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： B100、题目 W1-13 ：〔 2〕〔〕A ． AB． BC． CD． D标准答案： D。

东北农业大学网络教育学院耕作学作业题（一）一、解释名词1、耕作学：亦称农作学，是研究建立合理耕作制度（亦称农作制度）的理论及其技术体系的学科。

2、种植制度：是指一个地区或某个生产单位的作物种植结构及其在空间（地域或地块）对时间（季节、年代）上的安排。

3、单作：在一块地上一年或一季只种一种作物的种植方式，又称清种，华北称平作。

4、间作在同一块地上成行或带状（若干行）间隔种植两种或两种以上（通常为两种）生育季节相近（亦有不相近者）的作物。

二、简述题1、简述农业生产的严格地域性。

答：农业生产，是通过动植物的生命活动和环境资源进行物质和能量交换过程中实现的。

因此，环境是向植物提供所需生活因素的质和量是形成产量的客观条件。

环境的异质性，不仅存在于大自然区域之间，甚至在小范围内，由于小气候和土壤变化的相互作用常常引起环境生产潜力的巨大差异，要求完全不同的管理技术和利用途径。

因而农业生产具有严格的地域性。

2、简述我国粮食生产发展的四阶段。

答：1949-1958年为第一阶段，粮食产量达2亿吨；1959-1978年为第二阶段，粮食产量跃上了3亿吨；1979-1984年为第三阶段，粮食产量达4亿吨；1985-1996年为第四阶段，粮食产量跃上5亿吨。

3、简述农业生产应用连作的原因。

答：第一，在某些地区，气候和土壤条件比较适宜某种作物的种植。

第二，专业化程度高，生产者掌握其高产栽培技术，累积了丰富的高产稳定经验。

第三，在一些生产单位，适合于某一作物种植的机械化程度较高，种植作物种类少，相应的机械设备投资就少，降低了生产成本，提高了经济效益。

在商品生产较高的地区，为了赚取更多的利润，不可避免地出现商品性作物的连作。

第四，农田基本建设的改善和某些新技术的应用，克服了连作中产生的问题。

第五，不同作物对连作的反应不同，这是连作大量存在的原因。

三、论述题1、试论述垄作耕法中扣种的作业方法，以及垄作耕法的优缺点。

答：（1）扣种是一种垄耕作业，其方法有很多种，主要用于大粒种子作物，如玉米、大豆等。

专业资料整理完美WORD格式东北农业大学网络教育2018年专科起点本科入学测试模拟试题高等数学（一）一、选择题：在每个小题给出的四个选项中，只有一项是符合题目要求的。

1. （）A. B.1C. D.2. 设函数，在处连续，则（）A. B.C.D.3.设函数，则（）A. B.C. D.4. 设函数，则（）A.B. C.D.5. （）A. B.C. D.6. （）A. B. C. D.7. 设函数，则（）A. B. C. D.8. （）A. B. C. D.9. 设函数，则（）A.B.C. D.10. 若，则（）A. B.C.D.二、填空题：请把答案填在题中横线上。

11. .12. 设函数，则.13. 设事件发生的概率为0.7，则的对立事件发生的概率为.14. 曲线在点（1，0）处的切线方程为.15. .。

16. .17. 设函数，则.18. 设函数，则.19. 已知点（1，1）是曲线的拐点，则.20．设是由方程所确定的隐函数，则.三、解答题：解答应写出推理，演算步骤。

21.（本题满分8分）计算.22.（本题满分8分）设函数，求.23. （本题满分8分）设函数，求，.24. （本题满分8分）计算.25. （本题满分8分）计算.26. （本题满分10分）求曲线，直线和轴所围成的有界平面图形的面积及该平面图形绕轴旋转一周所得旋转体的体积.27. （本题满分10分）设函数，求的极值点与极值.28 . （本题满分10分）（1）求常数；（2）求的数学期望及方差.专业资料整理完美WORD 格式东北农业大学网络教育2018年专科起点本科入学测试模拟试题高等数学（一）参考答案1. C2. C3. A4. B5. B6. A7. D8. C9.A 10. D 11. 12. 13. 14. 15. 16. 17. 18.19. 20. 21. 解22. 解23. 解624. 解25. 解26. 解 面积旋转体的体积27. 解 由已知，，令 得驻点（0，0） 的2阶偏导数为，，故，，因为且所以（0，0）为的极小值点，极小值为28. 解 （1）因为，所以（2）东北农业大学网络教育2018年专科起点本科入学测试模拟试题高等数学（二）一、选择题：在每个小题给出的四个选项中，只有一项是符合题目要求的，把所选项前的字母填在题后的括号内。

东北农业大学网络教育学院计算机应用基础网上作业题及参考答案第二章 Windows7操作系统及应用选择题1.计算机启动时，首先同用户打交道的软件是在它的帮助下才得以方便、有效地调用系统各种资源。

A.操作系统B.Word字处理软件C.语言处理程序D.实用程序2.下列系统软件与应用软件的安装与运行说法中，正确的是。

A.首先安装哪一个无所谓B.两者同时安装C.必须先安装应用软件，后安装并运行系统软件D.必须先安装系统软件，后安装应用软件3.下列四种软件中属于应用软件的是。

A.BASIC解释程序B.WindowsC.财务管理系统D.Pascal编译程序4.新购置的裸机首先要安装。

A.字处理软件B.操作系统C.应用程序D.高级语言5.下列有关计算机程序的说法，正确的是。

A.程序都在CPU中存储并运行B.程序由外存读入内存后，在CPU中执行C.程序在外存储中存储并执行D.程序在内存中存储，在外存中执行6.下列有关计算机系统软件的叙述，正确的是。

A.提高计算机硬件资源的利用率，方便用户使用计算机B.清除病毒，维护计算机的正常运行C.开发电子商务系统D.解决语音输入7.操作系统功能包处理器管理、设备管理、存储管理、作业管理、文件管理，其中的“存储管理”主要是针对。

A.外存的管理B.辅助存储器的管理C.内存的管理D.内存和外存统一管理8.以下操作系统中，不是多任务操作系统的是。

A.MS-DOSB.Windows XPC.Windows 7D. Linux9.未装入软件的计算机是无法工作的。

A.汉字系统B.操作系统C.数据库管理系统D.Word200310.下列四种操作系统，以“及时响应外部事件”为主要目标的是。

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版更新高等数学作业题参考答案Revised on July 13, 2021 at 16:25 pm东北农业大学网络教育学院高等数学作业题2014更新版一、单项选择题 1. x y 1sin=在定义域内是 ..A. 单调函数B. 周期函数C. 无界函数D. 有界函数 2. 24lim22--→x x x =A . -6 B. 4 C. 0 D . 23. x e x f 2)(=;则)1(f '= A . 2e B . 22e C. e D. 2 4. ⎰=dx e xA ．2Ce x +B ．2C e x + C ．C e x +D ．C e x 1+ 5. 若曲线上任一点切线的斜率与切点横坐标成正比;则这条曲线是A.圆B.抛物线C.椭圆D.双曲线6. 下列函数是初等函数的是 .. A.3sin -=x y B.1sin -=x y C.⎪⎩⎪⎨⎧=≠--=1,01,112x x x x y D. ⎩⎨⎧≥<+=0,0,1x x x x y 7. x xx sin lim0→的值为 .. A.1 B.∞ C.不存在 D.08. )12ln(-=x y ;则)1(f '=A . 0 B. 2 C. 1 D. 39. 若()()x fxF=';则()()=⎰dxxfdA. ()x fB.()dxxf C. ()xF D. ()dxxF10. 方程2=-'yy的通解是Axy sin= B xey24= C xcey2= D x ey=11. 下列函数是初等函数的是 ..A.3sin-=xyB.1sin-=xyC.⎪⎩⎪⎨⎧=≠--=1,1,112xxxxyD. ⎩⎨⎧≥<+=,,1xxxxy12. x xx2 sinlim→A. 1B. 2C. 0D. 1-13.)12ln(-=xy;则)1(f'=A . 0 B. 2 C. 1 D. 314. 若()()x fxF=';则()()=⎰dxxfdA. ()x fB.()dxxf C. ()xF D. ()dxxF15. 方程2=-'yy的通解是Axy sin= B xey24= C xcey2= D x ey=16. 下列函数是初等函数的是 ..A.3sin-=xyB.1sin-=xyC.⎪⎩⎪⎨⎧=≠--=1,1,112xxxxyD. ⎩⎨⎧≥<+=,,1xxxxy17. 下列函数在指定的变化过程中; 是无穷小量..A．e1x x,()→∞B.sin,()xxx→∞C. ln(),()11+→x xD.x x x +-→110,() 18. )12ln(-=x y ;则)1(f '=A . 0 B. 2 C. 1 D. 319. 若()()x f x F =';则()()=⎰dx x f d A. ()x f B. ()dx x f C. ()x F D. ()dx x F20. 微分方程⎩⎨⎧==+0)1(3'y y xy 的解是 A ．)11(3x y -= B. )1(3x y -= C. x y 11-= D .x y -=121. 下列函数是初等函数的是 .. A.3sin -=x y B.1sin -=x y C.⎪⎩⎪⎨⎧=≠--=1,01,112x x x x y D. ⎩⎨⎧≥<+=0,0,1x x x x y 22. x xa x sin lim-∞→等于 .. A. a B. 0 C. -a D. 不存在23. 3ln -=y ;则dy =A . dx 3B . dx 31- C. dx 31 D. 024. ⎰=dx e xA ．2Ce x +B ．2C e x + C ．C e x +D ．C e x 1+ 25. 微分方程xdx dy 2=的解是A 、x y 2=B 、x y 2-=C 、2x y =D 、x y -=二、填空题1. 函数1142-+-=x x y 的定义域是_______.. 2. 32+=x y 的间断点是_______..3. 设函数)(x f y =在点x 可导;则函数)()(x kf x g =k 是常数在点x 可导、不可导.. 4. 设在),(b a 内曲线弧是凸的;则该曲线弧必位于其上每一点处的切线的 方..5. 在空间直角坐标系OXYZ 下;方程422=+y x 表示的图形为___________； 6. 若一个数列{}n x ;当n 时;无限接近于某一个常数a ;则称a 为数列{}n x 的极限.. 7. )1ln(+-=x x y 在区间 内单调减少;在区间 内单调增加.. 8. y x yx z -++=11的定义域为___________； 9. x x x 1)21(lim 0+→=三、计算题 1. 1310)21(lim -→-xx x 2. 求函数22x y x +=的二阶导数x d yd 22..3. 试确定,,,c b a 使c bx ax x y +++=23有一拐点)1,1(-;且在0=x 处有极大值1.. 4. 判断广义积分dxx e x ⎰∞+-0的敛散性;若收敛;计算其值..5. 求函数133+-=x y y x z 的一阶偏导数 6. 改变二次积分⎰⎰x e dy y x f dx ln 01),(的次序7. 求微分方程0sin sin cos cos =+ydy x ydx x 的解 8. 4586lim 221+-+-→x x x x x9. 求函数5555++=x x y 的微分.. 10. 求x y 45-=在[]1,1-区间的最大值和最小值..11. 判断广义积分dxx e x ⎰∞+-0的敛散性;若收敛;计算其值..12. 求函数xy y x z 323--= 的一阶偏导数 13. 改变二次积分⎰⎰yy dx y x f dy ),(10的次序14. 求微分方程e y y y x y x ===2,ln sin 'π的解.. 15. 求函数2)1ln(++-=x x y 的定义域 16. 13lim 242+-+∞→x x x x x17. 求函数x x y sin 1cos 1+-=的微分..18. 求)1ln(4+=x y 在[]2,1-上的最大值与最小值.. 19. 判断广义积分dxx e x ⎰∞+-0的敛散性;若收敛;计算其值..20. 求函数133+-=x y y x z 的一阶偏导数 21. 改变二次积分⎰⎰y y dx y x f dy ),(10的次序22. 求微分方程0sin sin cos cos =+ydy x ydx x 的解 23. 1310)21(lim -→-xx x24. 求函数)2ln(3-=x y 的微分.. 25. 求函数x x y ln 22-=的单调性 26. 求函数13222++-=y xy x z 的全微分 27. 改变二次积分⎰⎰y y dx y x f dy ),(10的次序28. 求微分方程033'''=+-y y y 的解.. 29. x xx 23tan lim0→ 30. 求函数22x y x +=的二阶导数x d yd 22.. 31. 求函数323x x y -=的单调性 32. 判断广义积分dxx e x ⎰∞+-0的敛散性;若收敛;计算其值..33. 求函数xy y x z 323--= 的一阶偏导数 34. 求微分方程044''=+'-y y y 的解.. 四、求解题1. 求由参数方程()⎩⎨⎧-=+=t t y t x arctan 1ln 2所确定的函数的二阶 2. 求由曲线22x y =;2x y =与2=y 所围成的平面图形面积.. 3. 试求x y =''过点0;1;且在此点与直线12+=x y 相切的积分曲线 4. x x f 1)(=;求x x f x x f x ∆-∆+→∆)()(lim 05. 求由参数方程()⎩⎨⎧-=+=t t y t x arctan 1ln 2所确定的函数的二阶6. 求函数323x x y -=的单调区间7. 求由曲线22x y =;2x y =与2=y 所围成的平面图形面积..8. 一曲线通过点)3,2(;它在两坐标轴间的任意切线线段均被切点所平分;求这条曲线..9. 求由抛物线2x y =及其在点)41,21(处的法线所围成的平面图形的面积..10. 求一曲线;这曲线过点0;1;且它在点(,)x y 处的切线斜率等于y x -..11. 试求x y =''过点0;1;且在此点与直线12+=x y 相切的积分曲线五、应用题1. 要做一个容积为250立方米的无盖圆柱体蓄水池;已知池底单位造价为池壁单位造价的两倍;设池底单位造价为a 元;试将总造价表示为底半径的函数..2. 在边长为a 2的正方形铁皮上;四角各减去边长为x 的小正方形;试问边长x 取何值时;它的容积最大3. 把一个圆形铁片;自中心处剪去中心角为α的一扇形后;围成一个无底圆锥;试将此圆锥体积表达成α的函数..4. 求面积为s 的一切矩形中;其周长最小者.5. 要做一个底面为长方形的带盖的箱子;其体积为372cm ;其底边成2:1的关系;问各边的长怎样;才能使表面积为最小.6. 某车间靠墙盖一间长方形小屋;现有存砖只够砌20米长的墙壁;问应围成怎样的长方形;才能使这间小屋的面积最大 高等数学作业题参考答案2014更新版一、单项选择题1. D2. B3. B4. A5. B6. B7. A8. B9. B 10. C11. B 12. B 13. B 14. B 15. C16. B 17. D 18. B 19. B 20. A21. B 22. C 23. D 24. A 25. C二、填空题1. [)(]2,11,2 -2. 3-=x3. 可导4. 下5. 母线为z 轴;2240x y z ⎧+=⎨=⎩为准线的圆柱面6. 无限增大 或∞→7.)0,1(-；),0(+∞ 8. (){}x y x y x <<-,9. 2e三、计算题1. 解：131021lim -→⎪⎭⎫ ⎝⎛-x x x ⎪⎭⎫ ⎝⎛-⎪⎭⎫ ⎝⎛-⋅-→⎪⎭⎫ ⎝⎛-=13122021lim x x x x x ⎪⎭⎫ ⎝⎛+-⋅-→⎪⎭⎫ ⎝⎛-=2612021lim x x x x 61-=e 2. 解：x dx dy x 22ln 2+= 2)2(ln 2222+=x dx y d3. 解：b ax x y ++='232;a x y 26+='' 因为函数有拐点)1,1(-;所以⎩⎨⎧-==''1)1(0)1(y y ;即⎩⎨⎧-=+++=+11026c b a a因为在0=x 处有极大值1;所以0)0(='y ;即0=b ;带入上式得 4. 解：dx x e x ⎰∞+-00022|2e e +∞+∞==-=⎰ 5. 23323,3xy x y z y y x x z -=∂∂-=∂∂ 6. ⎰⎰---=221110),(y y dx y x f dy7. 解：分离变量得xdx ydy cot tan -=两边积分得⎰⎰-=xdx ydy cot tan从而)sin arccos(x C y = 8. 解：4586lim 221+-+-→x x x x x 12lim 1--=→x x x ∞=9. 解：dx x x dy x )5ln 551(254-= 10. 解：x y 452--=';无驻点;y '不存在的点为45=x ;但]1,1[45-∉=x 所以最大值是3)1(=-y ;最小值是1)1(=y11. 解：dx x e x ⎰∞+-00022|2e e +∞+∞==-=⎰ 12. y x x z 332-=∂∂ ;x y y z 32--=∂∂13. ⎰⎰=x x dy y x f dx 2),(1014. 解：分离变量得x dx y y dy sin ln =;两边积分得⎰⎰=x dx y y dy sin ln 两边积分得⎰⎰=x dx y y dy sin ln ;从而原方程的特解为2tan x e y =.. 15. 解：120201<≤-⇒⎩⎨⎧≥+>-x x x16. 解：13lim 242+-+∞→x x x x x 22/13/11lim x x x x +-+=∞→0=17. 解：dx x x dy '⎪⎭⎫ ⎝⎛+-=sin 1cos 118. 解：1443+='x x y ;令0='y ;求得驻点为0=x 所以最大值是17ln )2(=y ;最小值是0)0(=y19. 解：dx x e x ⎰∞+-00022|2e e +∞+∞==-=⎰ 20. 23323,3xy x y z y y x x z -=∂∂-=∂∂21.⎰⎰=xxdyy x f dx 2),(1022. 解：分离变量得xdx ydy cot tan -=两边积分得⎰⎰-=xdxydy cot tan从而)sin arccos(x C y = 23. 解：13121lim -→⎪⎭⎫ ⎝⎛-xx x⎪⎭⎫⎝⎛-⎪⎭⎫ ⎝⎛-⋅-→⎪⎭⎫ ⎝⎛-=13122021lim x x x x x ⎪⎭⎫ ⎝⎛+-⋅-→⎪⎭⎫ ⎝⎛-=2612021lim x x x x 61-=e24. 解：dxx x dy 2332-= 25. 定义域为),0(+∞21,21,014142-===-=-='x x x x x x y 舍去)(,0),21,0(x f y <'为单调减函数 )(,0),,21(x f y >'+∞为单调增函数 26. yx x z 34-=∂∂y x y z 23+-=∂∂27.⎰⎰=xxdyy x f dx 2),(1028. 解：该方程的特征方程为0332=+-λλ;解得i2323±=λ..故原方程的通解为)23sin 23cos(2123x C x C e y x +=..29. 解：x x x 23tan lim0→ x x x 23lim0→= 23= 30. 解：x dx dy x22ln 2+= 2)2(ln 2222+=x dx y d31. 定义域为),(+∞-∞)(,0),0,(x f y <'-∞为单调减函数 )(,0),2,0(x f y >'为单调增函数 )(,0),,2(x f y <'+∞为单调减函数32. 解：dx xe x⎰∞+-22|2e e +∞+∞==-=⎰33. yx x z 332-=∂∂ ;x y y z 32--=∂∂34. 解：该方程的特征方程为0442=+-λλ;解得21=λ;22-=λ..故原方程的通解为)(212x C C e y x +=..四、求解题1. 解：2))1(ln()arctan (2tt d t t d dx dy =+-= 2. 解：求得交点)2,1(),2,1(-3. 解：1221C x xdx dx y y +==''='⎰⎰由题意1)0(=y ;21)0(='y ;代入解得211=C ;12=C ;即121613++=x x y ..4. 解：()()()200011lim 11lim lim x x x x x x x x x x f x x f x x x -=∆+-=∆-∆+=∆-∆+→∆→∆→∆ 5. 解：2))1(ln()arctan (2t t d t t d dx dy =+-=6. 解:函数323x x y -=的定义域是()+∞∞-,)2(3362--=-='x x x x y ;令0='y ;求得驻点为2,0==x x,0),0,(<'-∞∈y x 函数单调递减 ,0),2,0(>'∈y x 函数单调递增,0),,2(<'+∞∈y x 函数单调递减7. 解：求得交点)2,1(),2,1(-8. 解：设),(00y x 为曲线上的一点;函数过该点处的切线方程为))((000x x x f y y -'=-该切线与x 轴的交点为)(000x f y x '-;由题意0000))((21x x f y x ='-;简化得000)(x y x f -=' ),(00y x 的选取是任意的;∴所求曲线满足x y x f -=')(;解得x Cy 1= ..又3)2(=y ;x y 6=∴..9. 解：因为x y 2=';所以1)21(='y ; 抛物线2x y =在点)41,21(处的法线方程为 )21)(1(41--=-x y ;即43+-=x y 求得抛物线与其法线的交点为)41,21(),49,23(-;图形面积⎰-=-+-=2123234)43(dx x x S10. 解：由题意y x y -=';1)0(=y ..方程y x y -='对应的齐次方程为y dx dy -=;分离变量得dx y dy -=;解得xCe y -=..设原方程的解为xe x h y -=)(;代入原方程得xy e x h dx dx =+-))((;解得xx x x Ce x e C e xe y --+-=+-=1)(..又1)0(=y 得2=C ;从而原方程的解为xe x y -+-=21..11. 解：1221C x xdx dx y y +==''='⎰⎰由题意1)0(=y ;21)0(='y ;代入解得211=C ;12=C ;即121613++=x x y ..五、应用题1. 解：设池底半径为x 米;总造价为y 元)250(2r r a +=π;0>r2. 解：根据题意可知;容积2)22(x a x V -=;),0(a x ∈)22)(62()(x a x a x V --=';令0)(='x V ;求得驻点为3ax =;a x =舍去3a x =是开区间内唯一驻点;由实际问题可知容积有最大值;所以在边长3ax =时容积最大..3. 解：设圆锥体积为V;圆形铁片半径为R ;则圆锥底面半径πα2R r =;高22222⎪⎭⎫ ⎝⎛-=-=παR R r R h 所以圆锥体积22223242431αππαπ-==R h r V ;)2,0(πα∈4. 解:设矩形的长为x ;则宽为x s周长)(2x sx l +=;0>x )1(22x s l -=';令0='l ;求得驻点为s x =;0)(>''s l开区间内唯一驻点取得最小值;所以其周长最小者是长和宽都为s 的矩形..5. 解：设底边长为x x 2,..高为h所以x=3时取最小值;各边长分别为3;4;66. 解：设宽为x 米;则长为x 220-米;面积x x x x x S 202)220()(2+-=-=;)10,0(∈x 204)(+-='x x S ;令0)(='x S ;驻点为5=x04)5(<-=''S ;开区间内唯一驻点取得最大值;此时小屋的长为10米;宽为5米..。

东北农业大学入学测试机考专升本高等数学模拟试题1、题目 Z1-2（ 2）（）A ． AB．BC．CD． D标准答案： A2、题目 20－ 1：（ 2）（）A ． AB ．BC．CD． D标准答案： A3、题目 20－ 2：（ 2）（）A ． AB．BC．CD． D标准答案： B4、题目 20－ 3：（ 2）（）A ． AB ．BC．CD． D标准答案： A5、题目 20－ 4：（ 2）（）A ． AB ．BC．CD． D标准答案： D6、题目 20－ 5：（ 2）（）A ． AB．BC．CD． D标准答案： D7、题目 20－ 6：（ 2）（）A ． AB ．BC．CD． D标准答案： A8、题目 20－ 7：（ 2）（）A ． AB ．BC．CD． D标准答案： D9、题目 20－ 8：（ 2）（）A ． AB．BC．CD． D标准答案： C10、题目 11－1（ 2）（）A ． AB ．BC．CD． D标准答案： C11、题目 11－ 2（2）（）A ． AB．BC．CD． D标准答案： B12、题目 11－3（ 2）（）A ． AB ．BC．CD． D标准答案： A13、题目 20－ 9：（2）（）A ． AB．BC．CD． D标准答案： C14、题目 11－4：（ 2）（）A ． AB ．BC．CD． D标准答案： D15、题目 11－5（ 2）（）A ． AB ．BC．CD． D标准答案： C16、题目 20－ 10：（2）（）A ． AB ．BC．CD． D标准答案： B17、题目 11－6（ 2）（）A ． AB．BC．CD． D标准答案： B18、题目 11－7（ 2）（）A ． AB．BC．CD． D标准答案： C19、题目 11－8（ 2）（）A ． AB ．BC．CD． D标准答案： C20、题目 11－9（ 2）（）A ． AB．BC．CD． D标准答案： D21、题目 11－10（ 2）（）A ． AB ．BC．CD． D标准答案： B22、题目 19－ 1：（2）（）A ． AB．BC．CD． D标准答案： C23、题目 19－ 2：（2）（）A ． AB ．BC．CD． D标准答案： B24、题目 19－ 3：（2）（）A ． AB．BD． D标准答案： D25、题目 12－ 1（ 2）（）A ． AB ．BC．CD． D标准答案： D26、题目 12－ 2（ 2）（）A ． AB ．BC．CD． D标准答案： D27、题目 19－ 4：（2）（）A ． AB．BC．CD． D标准答案： B28、题目 12－ 3（ 2）（）B ．BC．CD． D标准答案： B29、题目 12－ 4（ 2）（）A ． AB ．BC．CD． D标准答案： C30、题目 12－ 5（ 2）（）A ． AB ．BC．CD． D标准答案： A31、题目 19－ 5：（2）（）A ． AB．BC．C标准答案： C32、题目 12－ 6（ 2）（）A ． AB ．BC．CD． D标准答案： A33、题目 12－ 7（ 2）（）A ． AB ．BC．CD． D标准答案： B34、题目 19－ 6：（2）（）A ． AB．BC．CD． D标准答案： B35、题目 12－ 8（ 2）（）A ． AB ．BC．CD． D标准答案： B36、题目 19－ 7：（2）（）A ． AB ．BC．CD． D标准答案： B37、题目 12－ 9（ 2）（）A ． AB．BC．CD． D标准答案： A38、题目 12－ 10（2）（）A ． AB ．BC．CD． D标准答案： C39、题目 19－ 8：（2）（）A ． AB．BC．CD． D标准答案： D40、题目 19－ 9：（2）（）A ． AB ．BC．CD． D标准答案： A41、题目 19－ 10：（2）（）A ． AB．BC．CD． D标准答案： C42、题目 18－ 1：（2）（）A ． AB ．BC．CD． D标准答案： A43、题目 18－ 2：（2）（）A ． AB ．BC．CD． D标准答案： C44、题目 18－ 3：（2）（）A ． AB ．BC．CD． D标准答案： D45、题目 13－ 1（ 2）（）A ． AB．BC．CD． D标准答案： D46、题目 18－ 4：（2）（）A ． AB ．BC．CD． D标准答案： A47、题目 13－ 2（ 2）（）A ． AB ．BC．CD． D标准答案： B48、题目 13－ 3（ 2）（）A ． AB．BC．CD． D标准答案： D49、题目 18－ 5：（2）（）A ． AB ．BC．CD． D标准答案： D50、题目 13－ 4（ 2）（）A ． AB ．BC．CD． D标准答案： B51、题目 13－ 5（ 2）（）A ． AB．BC．CD． D标准答案： D52、题目 18－ 6：（2）（）A ． AB ．BC．CD． D标准答案： B53、题目 13－ 6（ 2）（）A ． AB ．BC．CD． D标准答案： C54、题目 13－ 7（ 2）（）A ． AB ．BC．CD． D标准答案： C55、题目 18－ 7：（2）（）A ． AB．BC．CD． D标准答案： B56、题目 18－ 8：（2）（）A ． AB ．BC．CD． D标准答案： B57、题目 13－ 8（ 2）（）A ． AB ．BC．CD． D标准答案： B58、题目 13－ 9（ 2）（）A ． AB ．BC．CD． D标准答案： C59、题目 18－ 9：（2）（）A ． AB．BC．CD． D标准答案： B60、题目 13－ 10（2）（）A ． AB ．BC．CD． D标准答案： A61、题目 18－ 10：（2）（）A ． AB ．BC．CD． D标准答案： A62、题目 17－ 1：（2）（）A ． AB．BC．CD． D标准答案： C63、题目 17－ 2：（2）（）A ． AB ．BC．CD． D标准答案： D64、题目 17－ 3：（2）（）A ． AB ．BC．CD． D标准答案： C65、题目 17－ 4：（2）（）A ． AB．BC．CD． D标准答案： A66、题目 17－ 5：（2）（）A ． AB ．BC．CD． D标准答案： D67、题目 14－ 1（ 2）（）A ． AB ．BC．CD． D标准答案： D68、题目 14－ 2（ 2）（）A ． AB ．BC．CD． D标准答案： A69、题目 17－ 6：（2）（）A ． AB．BC．CD． D标准答案： B70、题目 14－ 3（ 2）（）A ． AB ．BC．CD． D标准答案： D71、题目 17－ 7：（2）（）A ． AB ．BC．CD． D标准答案： B72、题目 14－ 4（ 2）（）A ． AB ．BC．CD． D标准答案： C73、题目 14－ 5（ 2）（）A ． AB．BC．CD． D标准答案： C74、题目 17－ 8：（2）（）A ． AB ．BC．CD． D标准答案： D75、题目 14－ 7（ 2）（）A ． AB．BC．CD． D标准答案： A76、题目 14－ 8（ 2）（）A ． AB．BC．CD． D标准答案： D77、题目 17－ 9：（2）（）A ． AB ．BC．CD． D标准答案： B78、题目 14－ 9（ 2）（）A ． AB ．BC．CD． D标准答案： C79、题目 14－ 10（2）（）A ． AB．BC．CD． D标准答案： A80、题目 17－ 10：（2）（）A ． AB ．BC．CD． D标准答案： C81、题目 16－ 1：（2）（）A ． AB ．BC．CD． D标准答案： D82、题目 16－ 2：（2）（）A ． AB．BC．CD． D标准答案： B83、题目 16－ 3：（2）（）A ． AB ．BC．CD． D标准答案： C84、题目 15－ 1（ 2）（）A ． AB．BC．CD． D标准答案： C85、题目 15－ 2（ 2）（）A ． AB．BC．CD． D标准答案： C86、题目 16－ 4：（2）（）A ． AC．CD． D标准答案： D87、题目 15－ 3（ 2）（）A ． AB ．BC．CD． D标准答案： D88、题目 15－ 4（ 2）（）A ． AB．BC．CD． D标准答案： B89、题目 15－ 5（ 2）（）A ． AB．BC．CD． D标准答案： B90、题目 15－ 6（ 2）（）B ．BC．CD． D标准答案： A91、题目 15－ 7（ 2）（）A ． AB ．BC．CD． D标准答案： C92、题目 15－ 8（ 2）（）A ． AB ．BC．CD． D标准答案： C93、题目 16－ 5：（2）（）A ． AB．BC．CD． D标准答案： A94、题目 15－ 9（ 2）（）A ． AB ．BC．CD． D标准答案： B95、题目 15－ 10（2）（）A ． AB ．BC．CD． D标准答案： D96、题目 16－ 6：（2）（）A ． AB．BC．CD． D标准答案： B97、题目 16－ 7：（2）（）A ． AB ．BC．CD． D标准答案： C98、题目 16－ 8：（2）（）A ． AB ．BC．CD． D标准答案： B99、题目 16－ 9：（2）（）A ． AB ．BC．CD． D标准答案： A100、题目 16－ 10：（ 2）（）A ． AB．BC．CD． D标准答案： D。

通信原理专升本模拟题及详细答案东北农业⼤学⽹络教育学院通信原理专升本作业题作业题（⼀）⼀：填空题1已知f(t)的傅⽴叶变换F(w),则kf(t)傅⽴叶变换为（）2相⼲解调的关键是产⽣⼀个（）（）的载波3设信号()())500sin(100200cos 2wt wt t x +=,它的最低抽样频率为（）4差错控制编码是对数字信号进⾏（）编码，它是（）编码。

5循环码是⼀种系统码，它不同于其他线性分组码的⼀个特点是它的（）性6⽆码间串扰的传输条件是（）。

7调制的⽬的是（）8按照（）差错控制编码可分为卷积码和分组码9⾃相关函数是（）函数，它在（）的值最⼤.10wt t f sin )(的希尔伯特变换为（）⼆：选择题1 模拟通信系统的质量指标⽤（）来衡量。

A 有效性，可靠性B 适应性，标准性C 经济性，适应性D 标准性，经济性2 ⾮线性调制分为（）和（）。

A 调频，调幅B 调频，调相C 调相，调幅D FSK,PSK3 下列说法正确是A ()()0,1=∞-=∞F F X XB ()()1,1=∞-=∞F F XX C ()()0,0=∞-=∞F F X X D ()()1,0=∞-=∞F F XX 4对⾼斯过程⽽⾔，⼴义平稳和狭义平稳是（）的，也即若⾼斯过程是⼴义平稳的，则它⼀定是（）的。

A 等价的，狭义平稳B 不等价的，⼴义平稳C 不能确定，不能确定D 不等价, 不能确定5由 n 级移位寄存器产⽣的m 序列，其周期为（），它的⾃相关有（）种取值A 2n ，2B 2+n ，2C 4n ，4 D12-n , 2 6 PCM 过程主要包括抽样（）（）A 量化，编码B 调频，调相C 调相，调幅D 抽样，调频7 已知⼀个奇偶检验码为1101011，它是（）检验码A 奇B 偶C ⾮奇⾮偶D 不能确定8 抽样是把（）连续的模拟信号转换为时间上（）的量化信号A 幅度，连续B 时间，连续C 幅度，离散D 时间，离散9 图书编号为ISBN 7-5053-0714-2（）国际统⼀图书编号A 是B 不是C 不确定D 可能是10 若对所有的t, ()012=t R ,则两个信号为（） A 互相关 B 独⽴ C 互不相关 D 不确定三：简答题1 试简述检错重发系统的三种⽅式的⼯作过程2 简述门限效应的定义及其特点3简答数字基带信号的码型设计的原则4 试简述误⽐特率和误码率的定义及其⼆者的关系四：解答题1，某离散信源由0，1，2，3四个符号组成，他们出现的概率分别为3/8,1/4,1/4,1/18,且每个符号出现的都是独⽴的，求消息201020130213001203210100321010023102002010312032100120210的信息量。

东北农业大学网络教诲学院招生考试专升本模仿试题英语试题（一）I. Phonetics (5 points)Directions：In each of the following groups of words，there are four underlined letters or letter combinations marked A，B，C and D. Compare the underlined parts and identify the one that is different from the others in pronunciation. Mark your answer by blackening the corresponding letter on the Answer Sheet.1. A. out B. shout C. route D. about2. A. won B. done C. dozen D. pot3. A. engine B. end C. envelope D. effect4. A. program B. nature C. land D. lamb5. A. gave B. save C. salad D. hateII. Vocabulary and Structure (15 points)Directions：There are 15 incomplete sentences in this section. For each sentence there are four choices marked A，B，C and D. Choose one answer that best completes the sentence and blacken the corresponding letter on the Answer Sheet.6. He didn't keep on asking me the time any longer as he had had his watch .A. to repairB. repairedC. repairingD. repair7. The two strangers talked as if they friends for years.A. should beB. would beC. have beenD. had been8. His eyes shone brightly when he finally received the magazine he .A. had long been expectedB. had long expected.C. has long expectedD. was long expected9. What he said sounds .A. nicelyB. pleasantlyC. friendlyD. wonderfully10. The waiter was made to the guest.A. apologizeB. apologizingC. to apologizeD. to be apologizing11. It's believed that you work，result you'll get.A. the harder…the betterB. the more hard…the more betterC. the harder…a betterD. more hard…more better12. Young people may grow quickly in some ways and more slowly inA. the otherB. some otherC. othersD. these others13. We won't give up we should fail ten times.A. even ifB. sinceC. whetherD. until14. He'll be an astronaut by the time he thirty.A. isB. had beenC. will beD. is going to be15. He looked quite healthy though he was .A. in seventyB. in his seventyC. at seventiesD. at the age of seventy16. I need cloth，for I'm going to make clothes.A. a lot of…manyB. much…muchC. many... manyD. many... a lot of17. As soon as she entered the room，the girl caught sight of the flowers by her mother.A. buyingB. being boughtC. were boughtD. bought18. The boy ought to have gone to school but he slept noon.A. in that morning…atB. that morning…atC. in that morning…untilD. that morning…until19. If you really want yourself to be in good health，you must always so much.A. not…be smokingB. not…have smokedC. not…to smokeD. be not…smoking20. What impressed me most was that they never .A. lost heartsB. lost their heartC. lost heartD. lost their heartsIII. Cloze (30 points)Directions：For each blank in the following passage，there are four choices marked A，B，C and D. Choose the one that is most suitable and mark your answer by blackening the corresponding letter on the Answer Sheet.Most boys，and many girls too，have at some time or other started to have a hobby 21 popularity has 22 millions of millions of people in many countries throughout the world. The very hobby is stamp collection. Stamp-collecting，or，to call it 23 its correct name，philately (集邮) ，24 an increasing popular hobby from as 25 as 1854. It just took less than two 26 after postage stamps 27. Today the hobby 28 are not only boys and girls，but also men and women 29 all walksof life in society. So people want to share their passion with-the rest of the world. And other people want to show to other increase in the United States of America people how interesting and beautiful this hobby could be. So rapidly 30 the interest in stamp-collecting 31 in 1921 the United States Post Office found itself 32 set up a special department to 33 the needs of collectors. At present the yearly 34 of this department 35 over three hundred thousand dollars. And the same is true of some other countries. and in some the stamp sales have become an important source of national revenue.21. A. who B. that C. whose D. its22. A. keep affecting B. keep affect C. kept affecting D. kept being affected23. A. by B. in C. for D. with24. A. is B. has been C. was D. had been25. A. early B. late C. long D. far26. A. decade B. decides C. decades D. decay27. A. came into being B. came into use C. began using D. started to publish28. A. fans B. collectors C. citizens D. followers29. A. under B. from C. above D. with30. A. do B. an C. did D. had31. A. that B. so that C. where D. when32. A. should B. must C. liked to D. forced to33. A. fill B. push C. deal D. satisfy34. A. number B. amount C. money D. sales35. A. totally B. together C. totaling D. totalIV. Reading Comprehension (60 points)Directions：There are five reading passages in this part. Each passage is followed. by four questions. For each question there are four suggested answers marked A，B. C and D. Choose one best answer and blacken the corresponding letter on the Answer Sheet.Passage OneThe Great Crash of 1929 began on October 24. 1929.Fear seized the New York Stock Exchange (纽约股票交易市场). Investors wanted to sell their shares before the stock lost value. Over the next 5 days millions of shares flooded the market. Many investors lost all their money.During 1920s many Americans had invested in the stock market (股票市场). Many got rich.In 1928. Herbert Hoover was elected president. He said the future was bright with hope.People were being advised to buy stock before prices climbed even higher. Common sense was in short supply. Stock market rules let investors buy shares even if they did not have enough money. That is still true today but there are stronger controls.During the summer of 1929，some economists warned that there was no real value behind the high prices. President Hoover urged stock market officials to make trading safer and more honest. But he did not think the government should interfere in the market.When the drop in stock prices finally came，it was slow at first. It picked up speed (加速) as investors sold more and more shares. Several bankers bought stocks in an effort to prevent a crash. But the intense activity continued. October 29 is remembered as Black Tuesday. That day alone，stocks lost a tenth of their value.The crash (暴跌) caused a lot of people to lose their jobs，their farms and their homes. Many banks and businesses failed. The crash led to a worldwide depression (萧条) .36. The reason for the Great Crash is .A. that millions of shares flooded the marketB. Herbert Hoover was elected presidentC. the future was bright with hopeD. people kept buying stock before prices climbed even higher37. The government was responsible for the Great Crash of 1929 because .A. it urged stock market officials to make trading safer and more honestB. it did not interfere in the marketC. investors sold shares even if they did not have enough moneyD. fear seized the New York Stock Exchange38. The following are all true according to" the passage EXCEPTA. when the Great Crash came，it was slow at firstB. the Great Crash slowed down in speed as investors sold more and more sharesC. several bankers bought stocks in an effort to prevent a crashD. on October 29 alone，stocks lost a tenth of their value39. The passage mainly concentrates on .A. the context of the Great Crash of 1929B. the coming and going of the Great Crash of 1929C. the prosperous period of the AmericaD. the story of a stock marketPassage TwoThere are thousands of different languages in the world. Everyone seems to think that his native (本国) language is the most important one，as it is their first language. For many people it is even their only language all their lives. But English is the world's most widely used language.As a native language，English is spoken by nearly three hundred million people：in the U. S. ，England，Australia and some other countries.For people in India and many other countries，English is often necessary for business，education，information and other activities. So English is the second language there.As a foreign language，no other language is more widely studied or used than English. We use it to listen to the radio，to read books or to travel. It is also one of the working languages in the United Nations and is more used than the others.40. The native language is a person's language.A. firstB. onlyC. oneD. foreign41. People in use English as their second language.A. the U. S.B. IndiaC. ChinaD. Australia42. English is used working language in the United Nations.A. muchB. moreC. the moreD. the most43. English is used in ways by people all over the world.A. oneB. twoC. threeD. fourPassage ThreeWhen Walt Disney was drawing one night，he suddenly heard a strange sound. The sound came from the waste basket. Walt looked at it and saw a family of mice eating pieces of bread in it. For many nights，they played there. And Walt began to like them.Walt liked one little mouse better than any of the others. This little animal gave him some new ideas for his drawing. He began to draw it. But in the picture，it did not look like a mouse，but more like a funny man. He showed it to his wife and she liked it very much，too.Walt named this little m ouse “Mickey Mouse”. He hoped his Mickey Mouse would be different from the other pictures of his. He wanted to make Mickey talk. He put his fingers on his nose and made a strange sound. Then he recorded the voice this way. Later he sold his sound pictures to a cinema. When the film was shown，many people went to see it. Mickey Mouse in thefilm sang and danced and did all kinds of funny things. People couldn't help laughing when they saw it. It's a great success. Ever since then，Walt's Mickey Mouse has been one of the most famous film stars in the world.44. Walt was when he heard the strange sound.A. readingB. singingC. drawingD. playing45. The sound from the wastebasket was made by .A. some miceB. the waste paperC. the basketD. Walt Disney46. The mice were eating bread .A. on the tableB. on the plateC. in the basketD. on the floor47. Walt liked one little mouse .A. onlyB. bestC. betterD. the betterPassage FourIt was almost two 0' clock. A cold wind had come up over the lake. As a black cloud moved across the sun，Wait，a small boy，looked up. “I smell a storm (暴风雨) ,” he thought.Shorty，a man of forty，had gone into town. He had said he would be back before two. He had told Wait to watch the boats and the shop. There were no people around. They had all gone out on the lake to fish.So Wait went to work on one of the boats. From，there he could hear the telephone if it rang. And he could watch the door.It was a little after two when the stranger came. Wait saw him stop by the shop. The stranger looked in for a minute. Then he went down to the boats. He was a big man in a coat.Wait called to him，“Do you want something，sir?”The stranger looked at Wait and said，“No，thanks.” Then the stranger moved slowly away. As he went on，he looked at the boats one by one.Wait sat there with his eyes on the back of the stranger's coat. He thought，“I can smell something as I smell that storm. I hope Shorty comes back soon.”48. The story happened .A. on the lake at nightB. by the lake in the afternoonC. along the river in springD. near the river in summer49. Wait stayed because .A. there were no people aroundB. Shorty had gone shoppingC. people went fishing on the lakeD. Shorty had asked him to watch the boats and the shop50. Which of the following is true?A. The stranger came to see Wait.C. Wait worked far away from the shop.B. Shorty came back on time.D. Some people lived around the shop.51. At the end of the story Wait thoughtA. the stranger would not return againC. trouble might happen around the shopB. Shorty would not come back soonD. Shorty would lose his life in the stormPassage FiveMr. Brown was going away for a week. Before he left，he said to his son，“If anyone asks for me，you can tell him that your father has been out for doing something，and will be back in a week，then be sure to ask him to sit down for a cup of tea.”“OK，Dad,” said his son. But he was afraid his son couldn't remember this，he wrote these words down on a piece of paper and gave it to him. His son put it into his small pocket，took it out and looked at it every now and then.Four days passed，but no one came to see his father. The boy thought that there was no man to come and that the piece of paper was of no more use for him，so he burnt it that evening.The next afternoon，someone knocked at the door. The boy opened it. A man was standing at the door and said，“Where is your father?” the boy put his hand into his pocket at once and looked for the piece of paper. He could not find it. He suddenly remembered he had burnt it so he shouted，“No more.”The man was very surprised. He asked，“No more?I met your father last week. When did it happen?”“Burnt yesterday evening.”52. Mr. Brown told his son that .A. he would be away from home for four daysB. he would be back in seven daysC. he would be back in a monthD. he liked a cup of tea53. A man came to visit the boy's father on .A. the second dayB. the third dayC. the fourth dayD. the fifth day54. The man was very surprised because .A. he thought the child's father was deadB. the child didn't ask him to sit downC. the child gave him a cup of teaD. he couldn't find that piece of paper55. What was burnt?A. The piece of paper.B. Mr. Smith.C. The visitor.D. The boy.V. Daily Conversation (15 points)Directions：Pick out the appropriate expressions from the eight choices below and complete the following dialogues by blackening the corresponding letter on the Answer Sheet.A. Yes. It's very easy.B. Because of heavy fog.C. No，you'd better not.D. The great favorite of mine. G. Enjoy yourself.E. She's ill. Next week，maybe.F. The sooner the better. H. No. Thank you just the same.56. Bill：Do you think I should tell Jim the bad news?Alice：.57. Henry：Can you finish your homework tonight?Jane：.58. Joe：Why will the plane from New York be delayed?Ann：.59. Nancy：Why don't you call her and have a dinner together?Bob：.60. Pat：When do you want me to finish cleaning the office?Rose：.VI. Writing (2S points)Directions：For this part，yon are supposed to write a letter of 100-120 words based on the following situation. Remember to write it clearly.61. 你是李勇，上周错过了与Stella讨论她论文约会，写封信给她，内容涉及：(1) 对错过约会表达十分遗憾；(2) 当天你很早就乘公共汽车去赴约了；(3) 在路上出了事（如公共汽车与小汽车相撞，你右手受了重伤，被送到医院治疗）；(4) 告诉她近期无法再次约会，但愿她把有关资料用电子邮件发给你。

东北农业大学网络教育学院招生考试高升专模拟试题英语试题（二）(考试时间120分钟)Part I 语音知识（本题共10分，每小题1分）观察所给单词的读音，从A，B，C，D中找出其划线部分与所给单词的划线部分读音相同的选项。

1. avoid A. chat B. handsome C. tag D. apply2. involve A. honor B. consider C. connect D. control3. focus A. rude B. suggestion C. tutor D. subway4. science A. achieve B. variety C. movie D. brief5. surround A. proud B. enough C. cousin D. touch6. reporter A. worm B. forget C. airport D. world7. asked A. stressed B. believed C. satisfied D. minded8. chemical A. choose B. character C. change D. chief9. allow A. blow B. fellow C. however D. owner10. wood A. bloom B. too C. book D. shootPart II 阅读理解（本题共40分，每小题2分）阅读下列短文，并做每篇后面的题目。

从四个选项中，选出能回答所提问题或者完成所给句子的答案，并把答案划在答题纸的相应位置上。

Questions 11～15 are based on the following passage:Scientists have tried to come up with biological explanations for the difference between boys and girls. However, none were believable enough to explain the general picture. As one scientist points out, "There are slight genetic (遗传的) differences between the sexes at birth which may affect the subjects boys and girls choose. But the difficulty is that by the time children reach school age, there are so many other effects that it is almost impossible to tell whether girls are worse at science and math, or whether they've been brought up to think of these subjects as boys “…territory‟”Statistics show that in mathematics, at least, girls are equal to boys. A recent report suggests that girls only stop studying mathematics because of social attitudes. One of the reports' authors says, “While it is socially unacceptable for people not to be able to read and write, it is still acceptable for women to say that they are' hopeless, at math. Our research shows that, although girls get the explanation for the difference, which is very clear during the teenage years goes as far back as early childhood experiences.”From their first days in nursery school, girls are not encouraged to work on their own or to complete tasks, although boys are. For example, boys and girls are often asked to “help” with repair work. This en couragement leads to a way of learning how to solve problems, later in life. Evidence shows that exceptional mathematicians and scientists did not have teachers who supplied answers; they had to find out for themselves. A further report on maths teaching shows that teachers seem to give more attention to boys than to girls.Most teachers who take part in the study admitted that they expect their male students to dobetter at mathematics and science subjects than their female students. All of this tends to encourage boys to work harder in these subjects, gives them confidence and makes them believe that they can succeed.Interestingly, both boys and girls tend to regard such "male" subjects like mathematics and science as difficult. Yet it has been suggested that girls avoid mathematics courses, not because they are difficult, but for social reasons.Mathematics and science are mainly male subjects, and therefore, as girls become teenagers, they are less likely to take t hem up. Girls do not seem to want to be in open competition with boys. Neither do they want to do better than boys because they are afraid to appear less female and so, less attractive.11. The underlined word" territory" in the first paragraph most probably means .A. special fieldB. interestC. the landD. map12. According to scientific study, .A. math is not fit for girls to studyB. boys have a special sense of mathC. girls are poorer at math because they are the weaker sexD. girls can learn math as well as boys if given enough encouragement13. Those who made extraordinary contribution in mathematics and science .A. usually had good teachers to help themB. had the abilities to solve problems by themselvesC. usually worked harder than othersD. were encouraged to repair things when young14. Which of the following is NOT true according to the text?A. It is a social problem rather than a problem of brains that girls are poor at math.B. It seems socially acceptable for a girl not to be able to read and write.C. It is not easy for boys and girls to learn math and science.D. There is no connection between a girl's beauty and her ability.15. The best headline for the passage is .A. Are boys cleverer than girlsB. Who's afraid of scienceC. Girls are poorer at math than boys at math,D. Mat h－A Difficult SubjectQuestions 16～20 are based on the following passage:It was Monday. Mrs. Smith's dog was hungry, but there was not any meat in the house.Considering that there was no better way, Mrs. Smith took a piece of paper, and wrote the following words on it: “Give my dog half a pound of meat.” Then she gave the paper to her dog and said gently: “T ake this to the butcher, and he's going to give you your lunch today.”Holding the piece of paper in its mouth, the dog ran to the butcher's. It gave the paper to the butcher. The butcher read it carefully, recognized that it was really the lady's handwriting and soon did it as he was asked to. The dog was very happy, and ate the meat up at once.At noon, the dog came to the shop again. It gave the butcher a piece of paper again. After reading it, he gave 'it half a pound of meat once more.The next day, the dog came again exactly at noon. And as usual, it brought a piece of paper in the mouth. This time, the butcher did not take a look at paper, and gave the dog its meat, for he had regarded the dog as one of his customers (*people who buy sth. from a shop).But, the dog came again at four o'clock. And the same thing happened once again. To the butcher's more surprise, it came for the third time at six o'clock, and brought with it a third piece of paper. The butcher felt a bit puzzled. He said to himself, “This is a small dog. Why does Mrs Smith give it so much meat to eat today?”.Looking at the piece of paper, he found that there were not any words on it!16. Mrs. Smith treated her little dog quite .A. cruellyB. fairlyC. kindlyD. friendly17. It seemed that the dog knew well that the paper Mrs. Smith gave it .A. might do it much harmB. could do it much goodC. would help the butcherD. was worth many pounds18. The butcher did not give any meat to the dog .A. before he felt sure that the words were really written by Mrs SmithB. when he found that the words on the paper were not clearC. because he had sold out all the meat in his shopD. until he was paid enough by Mrs. Smith19. From its experience, the dog found that .A. only the paper with Mrs. Smith's words in it could bring it meatB. the butcher would give the meat to it whenever he saw itC. Mrs. Smith would pay for the meat it got from the butcherD. a piece of paper could bring it half a pound of meat20. At the end of the story, you'll find thatA. the dog was clever enough to write on the paperB. the dog dared not go to the butcher's any moreC. the butcher was told not to give any meat to the dogD. the butcher found himself cheated (*act in a way that is not honest) by the cleveranimalQuestions 21～25 are based on the following passage:Everything living on eart h－each plant and anima l－needs other living things. Nothing lives alone. Most animals must live in a group, and even a tree or a plant grows close together with others of the same kind. Sometimes one living thing hunts another, one eats and the other is eaten. Each kind of life eats another kind of life in order to live, and together they form a food chain (食物链). Some food chains are simple, others are complicated (复杂). But all have two things in commo n－all food chains begin with the sun, and all food chains become broken up if one of the links disappears.All, life depends on energy from sunlight. Only plants can use this energy directly. Their leaves are little factories that use sunlight to make food from water and things in the soil and air.Plants in turn feed all other living things. Animals can only use the sun's energy after it has been changed into food by plants. Some animals feed directly on plants, others eat smaller animals. Meat-eating animals are only eating plants indirectly.What about human beings? We are members of many food chains. We eat wheat, rice, vegetables, fruit and so on We also eat meat and drink milk. This means the sun's energy passes through plant to animal before it reaches us.Nature is a greater thing. Any food chain always produces enough for each of its members if it is left alone. When there isn't enough food for any link in the chain, some of its members die off. So the balance is always kept.But men in their greed(贪婪) and ignorance(无知) often break up the food chain and do great harm not only to one plant or animal, but to all the links in the chain. People make seas and rivers dirty. They destroy whole forests and kill many kinds of wild animals and birds. When a river becomes dirty, the fish cannot be eaten. Men eat the fish and get strange diseases. In some places men have no fish to eat any more, because the fish have died off. Each form of life is linked to all others. Breaking the links puts all life in danger.21. How does everything living on earth live?A. Each plant can live alone.B. Each animal can live alone.C. Everything living on earth can not live without needing other living things.D. If living things want to live they must kill each other.22. How is food for plants made? Food for plants is made .A. from waterB. from the air in the skyC. from the soilD. from water, things in the soil and air, sunlight23. How do all food chains break? All food chains are broken if .A. one kind of animal is eaten upB. one kind of plant is destroyedC. one kind of animal eats anotherD. one of the links is destroyed24. Which living things can use energy directly?A. Animals.B. Plants.C. Both animals and plants.D. All living things.25. Why is all life in danger? Because break up the food chains.A. human beingsB. animalsC. plants and animalsD. man and wild animalsQuestions 26～30 are based on the following passage:The whole body is covered with skin. The surface of the skin is dead (like the hair and the nails) , but it is made from a living layer(层) just under the surface. The outside dead layers wear off(磨损)all the time, with new ones replacing them, and the body forms a totally' new skin every three weeks.The skin protects the body from the outside world and it passes information, from the outside. It helps to keep water in the body and to keep the body at the same temperature. Bacteria (细菌) can't get in through the skin unless it is damaged.If the weather is cold, the blood vessels (血管) in the skin squeeze down, or contract (收缩) ,so that as little blood as possible comes near the surface. This means that less warmth is lost to the outside, This makes the ski1 look pale, or even “blue”. At the same time, the hairs on the skin are pulled upright by tiny muscles.When it is hot, the blood vessels expand (扩大),or get wider again, to allow plenty of blood to run near the surface of the skin. This helps the body to lose heat, and the skin may look red At the' same time, the sweat glands (汗腺)produce more sweat, which cools the skin.If your skin has ever been numb (麻木的), you will realize how important the feeling from the skin is. Nerves (神经) in the skin are sensitive(敏感的) to heat and cold, sharpness, hardness and softness, wetness and dryness and pain. If one is not able to feel these things, which can act as warnings, he is likely to be burned, cut or hurt in other ways.The colour of the skin depends on special colour cells (细胞). These are just below the top layers of the skin. They are needed as protection from some harmful ray of the sun. People with pale skins may “tan” (晒黑)in the sun. This happens when the body produces extra colour cells in the skin: for protection. In the sun, the skin produces a vitamin (vitamin D) which is needed for: strong bones.26. Which of the following statements is NOT true?A. Our hair and nails are dead like the surface of the skin.B. There is skin all over our body.C. The skin of our bodies will be completely different in three weeks.D. The surface of the skin is made of a living layer.27. The second paragraph mainly tells us about .A. the functions of the skinB. the information from the outsideC. the water in the bodyD. the temperature of the body28. Bacteria will get in through the skin .A. when one's skin is numbB. when one is illC. when the skin is cutD. when the sweat glands produce more sweat29. When the weather is cold, the skin will contract in order to .A. allow more blood is coldB. make the skin look blueC. keep warmthD. help the body lose heat30. The colour of the skin is determined by .A. the rays of the strong sunB. colour cellsC. top layers of the skinD. vitaminPart III 词汇和语法结构（本题共50分，每小题1分）从四个选项中，选出最佳答案划在答题纸的相应位置上。

注：装订线内禁止答题，装订线外禁止有姓名和其他标记。

东北农业大学网络教育学院在职高升专期末测试题23220007 高等数学一、填空题(每题2分，共5题)1. 函数1142-+-=x x y 的定义域是_[-2,1)Y(1,2]__2. x x x 1)21(lim 0+→=( 2e ) 3. 设函数)(x f y =在点x 可导，则函数)()(x kf x g =（k 是常数）在点x 可导 （可导、不可导）。

4. )1ln(+-=x x y 在区间 )0,1(- 内单调减少，在区间 ),0(+∞ 内单调增加。

5. y x y x z -++=11的定义域为(){}x y x y x <<-,；二、单项选择题(每题4分，共5题)1. 下列函数是初等函数的是（ B ）。

A.3sin -=x yB.1sin -=x yC.⎪⎩⎪⎨⎧=≠--=1,01,112x x x x y D. ⎩⎨⎧≥<+=0,0,1x x x x y2. x xx 2sin lim0→ （ B ） A. 1 B. 2 C. 0 D. 1-3. )12ln(-=x y ，则)1(f '=（ B ）A . 0 B. 2 C. 1 D. 34. 若()()x f x F ='，则()()=⎰dx x f d （ B ） A. ()x f B. ()dx x f C. ()x F D. ()dx x F5. 方程02=-'y y 的通解是（ C ）A x y sin =B x e y 24=C x ce y 2=D x e y =三、计算题(每题5分，共8题)注：装订线内禁止答题，装订线外禁止有姓名和其他标记。

1. 求函数2)1ln(++-=x x y 的定义域解：120201<≤-⇒⎩⎨⎧≥+>-x x x 2. 13lim 242+-+∞→x x x x x解：13lim 242+-+∞→x x x x x 22/13/11limx x x x +-+=∞→ 0= 3. 求函数x x y sin 1cos 1+-=的微分。

计算机⽹络技术专升本模拟题及参考答案东北农业⼤学⽹络教育学院计算机⽹络基础专升本作业题作业题（⼀）第⼀、⼆章⼀、名词解释：1、计算机⽹络：2、IP地址：3、协议：4、窄义的Internet：⼆、选择1.计算机⽹络的最突出的优点（）A.精度⾼B.内存容量⼤C.运算速度快D.共享资源2.组建⼴域⽹，经常采⽤的拓扑结构是（）A星型 B.⽹状型 C.环型 D.总线型3.计算机⽹络按其所涉及范围的⼤⼩和计算机之间互联的举例，其类型可分为（）A.局域⽹，⼴域⽹和混合⽹B.分布的，集中的和混合的C.局域⽹⼴域⽹D.通信⽹，因特⽹和万维⽹4.⽹络的存储类型有（）A.SNAB.INASC.SAND.IDE5.Inertnet上各种⽹络和各种不同类型的计算机相互通信的基础是（）A.HTTPB.IPXC.X.25D.TCP/IP/doc/bd37ff1c59eef8c75fbfb350.html 是Internet上⼀台计算机的（）A.域名B.IP地址C.⾮法地址D.协议名称7.合法的IP地址是（）A. 202:144:300:65B.202.112.144.70C. 202,112,144,70D.202.112.708.以下IPv6地址中，不合法的是（）A.2001:0250:0000:0001:0000:0000:0000:4567B.2001:250:0:1::4567C. 2001:250::1::4567D.::202.112.144.70三、判断题：1．计算机⽹络系统由⽹络硬件和⽹络软件两部分组成。

（）2．⽹络节点可分为两类:⼀类是转节点，它是信息交换的源点和⽬标，如服务器、⽹络⼯作站等；另⼀类是访问节点，它的作⽤是⽀持⽹络的连接，它通过通信线路转接和传递信息，如集中器、交换机等。

（）3．在环型结构的⽹络中，信息按固定⽅向流动，或顺时针⽅向，或逆时针⽅向。

（）4．IP地址是⼀个32位的⼆进制⽆符号数，为了表⽰⽅便，将32位地址按字节分为4段，低字节在前，每个字节⽤⼗进制数表⽰出来，并且各字节之间⽤点号“，”隔开。

东北农业大学网络教育2014年高中起点专科入学考试模拟试题数学（一）一、选择题：本大题共17小题，每小题5分，共85分。

在每小题给出的四个选项中，只有一项是符合题目要求的。

（1）设集合函数，，则（）（A）（B）（C）（D）（2）函数的最小正周期是（）（A）（B）（C）（D）（3）（）（A）（B）（C）（D）（4）不等式的正整数解是（）（A）1，2 （B）1，2，3 （C）1，2，3，4 （D）0，1，2，3，4（5）若是直线上的一点，则与的关系成立的是（）（A）（B）（C）（D）（6）等比数列中，若，，则（）（A）（B）（C）（D）（7）四名学生和两名教师排成一排，若教师不相邻且不排在两端，则不同的排法有（）（A）72种（B）96种（C）144种（D）240种（8）设，则等于（）（A）（B）（C）（D）（9）函数（）（A）是奇函数（B）是偶函数（C）既是奇函数又是偶函数（D）既不是奇函数又不是偶函数（10）5个人站成一排照相，甲、乙两个恰好站在两边的概率是（）（A）（B）（C）（D）（11）圆点在点且与直线，相切的圆的方程是（）（A）（B）（C）（D）（）（12）如果抛物线方程，那么它的焦点到准线的距离等于（）（A）2 （B）4 （C）8 （D）16（13）在等比数列中，，，则（）（A）（B）（C）（D）（14）函数的单调减区间是（）（A）（B）（C）（D）（15）已知函数的定义域为，则等于（）（A）（B）（C）（D）（16）已知椭圆则它的焦距等于（）（A）（B）（C）（D）（17）设，，成等比数列，则等于（）（A）4或―4 （B）4或―6（C）―4或6 （D）4或6二、填空题：本大题共4小题，每小题4分，共16分。

把答案填在题中横线上。

（18）。

（19）若函数是奇函数，且在[1，5]上是增函数，那么函数值与中较大的是。

（20）已知三角形三边分别为，，，这个三角形的最大角度是。

（21）从一个班级中任取18名学生，测得体育成绩如下（单位：分）81 76 85 90 82 79 84 86 8380 79 96 90 81 82 87 81 83样本方差等于。

东北农业大学网络教育学院离散数学复习题复习题一一、证明1、对任意两个集合B A 和，证明 ()()A B A B A =⋂⋃-答：证明：()()()()()A E AB B A B A B A B A B A =⋂=⋃⋂=⋂⋃⋂=⋂⋃- 2、构造下面命题推理的证明如果今天是星期三，那么我有一次英语或数学测验；如果数学老师有事，那么没有数学测验；今天是星期三且数学老师有事，所以我有一次英语测验。

答：符号化为：Q S P R S R Q P ⇒∧⌝→∨→,, 证明：(1)S P ∧ P (2)P T(1)I (3)S T(1)I (4)R Q P ∨→ P (5) R Q ∨ T(2)(4)I (6) R S ⌝→ P (7) ,R ⌝ T(3)(6)I (8)Q T(5)(7)I二 、计算1、(1)画一个有一条欧拉回路和一条汉密顿回路的图。

(2)画一个有一条欧拉回路但没有汉密顿回路的图(3)画一个没有欧拉回路但有一条汉密顿回路的图 答：三种图如下：2、设()(){}212,，，个体域为为，整除为<x x Q y x y x P ，求公式：()()()()()x Q y x P y x →∃∀,的真值。

答：()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()TT T F T T T F T F F T T T T Q P Q P Q P Q P x Q x P x Q x P x x Q y x P y x ⇔∧⇔∨∧∨⇔→∨→∧→∨→⇔→∨→∧→∨→⇔→∨→∀⇔→∃∀22,221,212,111,12,1,,3、一棵树有2n 个结点度数为2 ，3n 个结点度数为3，… ，k n 个结点度数为k ，问它有几个度数为1的结点。

答：设它有1n 个度数为1的结点，则：1*1n ＋2*2n ＋3*3n ＋… ＋k*k n =2*（1n +2n +3n +…+k n -1） 得：1n =3n ＋2*4n ＋… ＋(k-2)*k n +24、设集合{}A A ,4,3,2,1=上的关系 {4,33,2,1,22,11,1=R ，求出它的自反闭包，对称闭包和传递闭包。

东北农业大学(2021版)离散数学网上作业题及答案东北农业大学网络教育学院离散数学复习题复习题一一、证明1、对任意两个集合a和b，证明?a?ba?b??a答案：证据：？A.BA.BA.BA.BA.BBA.EA.2、构造下面命题推理的证明如果今天是星期三，那么我要参加英语或数学考试；如果数学老师有事要做，就没有数学考试；今天是星期三，数学老师很忙，所以我有一个英语考试。

A:符号化为：P？Qr、s？？r、 p？s问题证明：（1）P？sp（2）pt（1）i（3）st（1）i（4）p？Qrp（5）q？rt（2）（4）i（6）s？？rp（7）？r、 t（3）（6）i（8）qt（5）（7）i二、计算1.（1）用欧拉回路和汉密尔顿回路绘制图表。

（2）画一个有欧拉回路但没有汉密尔顿回路的图（3）画一个没有欧拉回路但有汉密尔顿回路的图a：三个图如下：1，2?，公式：2。

设定p？x、是吗？把y，Q除以X？十、是x吗？2.单个域为1x?yp?x,yq?x的真值。

十、YPx、是吗？？Q十、十、Px、 1？？Q十、Px、 2？？Q十、P1,1??Q1.P1,2?? Q1.P2,1?? Q2.P2,2?? Q2.答复:t?tt?t??f?ft?f?t?tt?f??t?t?t3、一棵树有n2个结点度数为2，n3个结点度数为3，?，nk个结点度数为k，问它有几个度数为1的结点。

答：假设它有阶数为1的N1个节点，那么：1*n1＋2*n2＋3*n3＋?＋k*nk=2*（n1+n2+n3+?+nk-1）得：n1=n3＋2*n4＋?＋(k-2)*nk+21,2,3,4?, 在r上谈恋爱？1,1,1,2,2,1,2,3,4，求其自反闭包、对称闭包和4。

设定一个？？通过关闭。

答：r(r)?1,1,1,2,2,1,2,3,3,4,2,2,3,3,4,4s（r）？？1,1,1,2,2,1,2,3,3,4,3,2,4,3?t(r)??1,1,1,2,2,1,2,3,3,4,1,3,2,2,2,4,1,4?三、设定一个？？1,2,3,5,6,9,15,27,36,45? R上的可除关系？a1，a2a1，a2？a、A1除以A2，r是否为a上的偏序关系？若是，然后：1。