已知函数 f(x)=x2+bx+c 满足 f(2−x)=f(2+x) ， f(0)>0 ，且 f(m)=f(n)=0 （ m≠n ），则 log4m−log14n 的值_刷题宝

题干

已知函数 f(x)=x2+bx+c 满足 f(2−x)=f(2+x) ， f(0)>0 ，且 f(m)=f(n)=0 （ m≠n ），则 log4m−log

1

4

n 的值（）

A：小于1

B：等于1

C：大于1

D：由 $b$ 的符号确定

上一题下一题 0.0难度选择题更新时间:2019-01-16 10:47:41

答案(点此获取答案解析）

A

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