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更多“Isshe__sister（）”相关的问题
可微函数f(x，y在点(xo，yo)取得极大值，下列结论正确的是()．
A．f(xo，y)在)y＝yo处的导数等于零
B．f(xo，y)在y＝yo处的导数大于零
C．f(xo，y)在y＝yo处的导数小于零
D．f(xo，y)在y＝yo处的导数不存在
设f(x，y)与φ(x，y)均为可微函数，且φˊ(x，y)≠0，已知(xo，yo)是f(x，y)在约束条件φ(x，y)＝0下的一个极值点，下列选项正确的是()．
A．若fˊx(x，yo)＝0，则fˊy(xo，yo)＝0
B．若fˊx(xo，yo)=0，则fˊy(xo，yo)≠0
C．若fˊx(xo，yo)≠0，则fˊy(xo，yo)＝0
D．若fˊx(xo，yo)≠0，则fˊy(xo，yo)≠0
设f(x，y)与φ(x，y)均为可微函数，且φˊy(x，y)≠0，已知(xo，yo)是f(x，y)在约束条件φ(x，y)＝0下的一个极值点，下列选项正确的是()．
A．若fˊx(xo，yo)＝0，则fˊy(xo，yo)＝0
B．若fˊx(xo，yo)＝0，则fˊy(xo，yo)≠0
C．若fˊx(xo，yo)≠0，则fˊy(xo，yo)＝0
D．若fˊx(xo，yo)≠0，则fˊy(xo，yo)≠0
A.File
B.provide
C.simplify
D.priority
You seldom go to the cinema on the weekends, ______ ？
A．don't you
B．will you
C．do you
D．did you
How long do you think ______ to finish this urgent task？
A．did it take you
B．it will take you
C．will it take you
D．it to take you
You seldom have to do the cooking,______？
A. have you
B. haven't you
C. do you
D. don't you
______you will never convince him.
A．However long you argue
B．However you argue long
C．How you argue long
D．How long you argue
In the last paragraph, the writer implies that active learning______.
A．is important for you to remember more within the shortest possible time
B．can not be easily accepted
C．may test material
D．is serviceable for reading and listening
