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David: Hi, Linda, what are you doing? Linda: Hi, David．I 小题1: （prepare） for the test tomorrow． David: But 小题2: are you sitting here in the garden? Linda: Well, the library is full and the classroom is too noisy． Are you ready 小题3: the test ?l David: I am afraid not．I feel very nervous． We don't have much time 小题4: （leave）． Linda: We can prepare together． Maybe that can help． David: Good idea． How many units will be included in 小题5: coming test? Linda: Three altogether． They are Unit 4,Unit5 and Unit 6． David: Really? I 小题6: （think） Unit 6 would not be covered． Linda: It is included 小题7: it is only partly finished by our teacher． Now let's ask each other questions．You go first． David: All right．Please name three European countries． Linda: It's easy． France, Germany and Russia．I 小题8: even say more． David: It seems you are 小题9: （well） prepared than me． Now it's 小题10: turn to ask me questions． Linda: OK． What are the seven continents of the world? David: Asia, Europe, Africa, and err．．．．I really can't remember them all． Linda: Don't worry． You still have some time today to prepare．
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【单选题】函数f(x,y)=4(x−y)−x2−y2f(x,y)=4(x−y)−x2−y2的极值为
A.
f ( 2 , − 2 ) = 8 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 2 , − 2 ) = 8 f(2,−2)=8
B.
f ( − 2 , − 2 ) = 0 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( − 2 , − 2 ) = 0 f(−2,−2)=0
C.
f ( 2 , 2 ) = 0 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 2 , 2 ) = 0 f(2,2)=0
D.
f ( − 2 , 2 ) = 8 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( − 2 , 2 ) = 8 f(−2,2)=8
【简答题】基准分为（）基准和（）基准两大类；工艺基准有（）基准，（）基准和（）基准.
【单选题】(2009年) 设z=f(x2一y2)，则dz等于( )。
A.
2x一2y
B.
2xdx一2ydy
C.
f’(x2一y2)dx
D.
2f’(x2一y2)(xdx—ydy)
【单选题】已知点P 1 （x 1 ，y 1 ）、P 2 （x 2 ，y 2 ）分别在直线l上和在l外，若直线l的方程为f（x，y）=0，则方程f（x，y）-f（x 1 ，y 1 ）-f（x 2 ，y 2 ）=0表示（ ）
A.
与l重合的直线
B.
与l平行，且过P 1 的直线
C.
与l平行，且过P 2 的直线
D.
同时过P 1 、P 2 的直线
【单选题】函数f(x,y)=(6x−x2)(4y−y2)f(x,y)=(6x−x2)(4y−y2)的极值为
A.
f ( 3 , 2 ) = 36 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 3 , 2 ) = 36 f(3,2)=36
B.
f ( 3 , 0 ) = 0 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 3 , 0 ) = 0 f(3,0)=0
C.
f ( 0 , 2 ) = 0 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 0 , 2 ) = 0 f(0,2)=0
D.
f ( 3 , 2 ) = 6 " role="presentation" style="display: inline-block; line-height: 0; font-size: 19.52px; overflow-wrap: normal; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; margin: 0px; padding: 1px 0px; color: rgb(0, 0, 0); font-family: "Microsoft YaHei"; position: relative;" > f ( 3 , 2 ) = 6 f(3,2)=6
【单选题】设函数f(x，y)为可微函数，且对任意的x，y都有 ，则使不等式f(x1，y1)＞f(x2，y2)成立的一个充分条件是( )．
A.
x1＞x2，y1＜y2
B.
x1＞x2，y1＞y2
C.
x1＜x2，y1＜y2
D.
x1＜x2，y1＞y2
【简答题】已知函数f（x）=（x 2 ﹣a）e x ． （1）若a=3，求f（x）的单调区间和极值； （2）若x 1 ，x 2 为f（x）的两个不同的极值点，且 ， 若 恒成立，求实数b的取值范围．
【简答题】设F(x，y)是一个二维随机向量(X，Y)的分布函数，x12，y12，证明： F(x2，y2) - F(x1，y2) - F(x2，y1)+F(x1，y1)≥0．
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