试题与答案

函数在点(0,0)处 (A) 连续,但偏导数f’x与f’y不存在. (B) 既不

题型:单项选择题

题目:

函数

在点(0,0)处
(A) 连续,但偏导数f’x与f’y不存在.
(B) 既不连续,偏导数f’x与f’y也不存在.
(C) 两个偏导数f’x与f’y都存在,但函数f(x,y)不连续.
(D) 可微分.

答案:

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