挑战习题
1/4单选题
难度:

1.

已知为R上的可导函数,当时,则函数的零点个数为(      )


A

1

B

2

C

0

D

0或2

提示1:
PHA+5p6E6YCg5Ye95pWwPC9wPg==
提示2:
PHA+5rGC5a+877yM6L+b6ICM5rGC5p6B5YC8PC9wPg==
正确答案:Qw==
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