挑战习题
1/3单选题
难度:

1.

已知函数f(x)的图象是连续不断的曲线,有如下的x与f(x)的对应值表

x1234567
132.115.4-2.318.72-6.31-125.112.6

那么,函数在区间[1,7]上的零点至少有(  )


A

5

B

4

C

3

D

2

提示1:
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
提示2:
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
正确答案:Qg==
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