电大工程数学(本)(09模拟试题(含答案)小抄参考

1、工程数学（本）(09秋模拟试题 2009年12月 一、单项选择题（每小题3分，本题共15分）1. 设为矩阵，为矩阵，当为（）矩阵时，乘积有意义a. b. c. d. 2. 向量组的极大线性无关组是（ ）a b c d.3. 若线性方程组的增广矩阵为，则当（）时线性方程组有无穷多解 a1 b4 c2 d4. 掷两颗均匀的骰子，事件“点数之和为4”的概率是（ ）.a. b. c. d. 5. 在对单正态总体的假设检验问题中，检验法解决的问题是（ ）a. 已知方差，检验均值 b. 未知方差，检验均值 c. 已知均值，检验方差 d. 未知均值，检验方差 二、填空题（每小题3分，共15分）1. 设均为3

2、阶矩阵，且，则2.设，则3. 设是三个事件，那么发生，但至少有一个不发生的事件表示为 .4. 设随机变量，则5. 设是来自正态总体的一个样本，则 三、计算题（每小题16分，共64分）1已知，其中，求2.求线性方程组的全部解 3. 设，求和.（其中,）4. 某一批零件重量，随机抽取4个测得重量（单位：千克）为14.7, 15.1, 14.8, 15.2 可否认为这批零件的平均重量为15千克(已知)？ 四、证明题（本题6分）设,为随机事件，试证： 工程数学（本）（09秋）模拟试题参考答案（供参考）2009年12月一、单项选择题（每小题3分，本题共15分） 1. b 2. a 3. d 4. c 5

3、. b二、填空题（每小题3分，本题共15分）1. 2. 23. 4. 5. 三、计算题（每小题16分，本题共64分）1. 解：利用初等行变换得即 由矩阵乘法运算得 2.解： 将方程组的增广矩阵化为阶梯形方程组的一般解为（其中为自由未知量） 令=0，得到方程的一个特解. 方程组相应的齐次方程的一般解为 （其中为自由未知量）令=1，得到方程的一个基础解系. 于是，方程组的全部解为 （其中为任意常数） 3. 解：设 = 4. 解：零假设由于已知，故选取样本函数经计算得，已知，故接受零假设，即可以认为这批零件的平均重量为15千克. 四、证明题（本题6分）证明：由事件的关系可知而，故由概率的性质可知即

4、证毕 if we dont do that it will go on and go on. we have to stop it; we need the courage to do it.his comments came hours after fifa vice-president jeffrey webb - also in london for the fas celebrations - said he wanted to meet ivory coast international toure to discuss his complaint.cska general dire

5、ctor roman babaev says the matter has been exaggerated by the ivorian and the british media.blatter, 77, said: it has been decided by the fifa congress that it is a nonsense for racism to be dealt with with fines. you can always find money from somebody to pay them.it is a nonsense to have matches p

6、layed without spectators because it is against the spirit of football and against the visiting team. it is all nonsense.we can do something better to fight racism and discrimination.this is one of the villains we have today in our game. but it is only with harsh sanctions that racism and discriminat

7、ion can be washed out of football.the (lack of) air up there watch mcayman islands-based webb, the head of fifas anti-racism taskforce, is in london for the football associations 150th anniversary celebrations and will attend citys premier league match at chelsea on sunday.i am going to be at the ma

8、tch tomorrow and i have asked to meet yaya toure, he told bbc sport.for me its about how he felt and i would like to speak to him first to find out what his experience was.uefa hasopened disciplinary proceedings against cskafor the racist behaviour of their fans duringcitys 2-1 win.michel platini, p

9、resident of european footballs governing body, has also ordered an immediate investigation into the referees actions.cska said they were surprised and disappointed by toures complaint. in a statement the russian side added: we found no racist insults from fans of cska.baumgartner the disappointing n

10、ews: mission aborted.the supersonic descent could happen as early as sunda.the weather plays an important role in this mission. starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. the balloon, with capsule attach

11、ed, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. it will climb higher than the tip of mount everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into t

12、he stratosphere. as he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence.the balloon will slowly drift to the edge of space at 120,000 feet ( then, i would assume, he will slowly step out onto something resembling an olympic diving platform.below, the earth becomes

13、the concrete bottom of a swimming pool that he wants to land on, but not too hard. still, hell be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. it will be like he is diving into the shallow end.skydiver preps for the big jumpwhen he jumps, he is exp

14、ected to reach the speed of sound - 690 mph (1,110 kph) - in less than 40 seconds. like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to earth. but this will not be enough to stop him completely.if he goes too fast or spins out of control, he has a st

15、abilization parachute that can be deployed to slow him down. his team hopes its not needed. instead, he plans to deploy his 270-square-foot (25-square-meter) main chute at an altitude of around 5,000 feet (1,524 meters).in order to deploy this chute successfully, he will have to slow to 172 mph (277 kph). he will have a reserve parachute that will open automatically if he loses conscio