定义函数y=f（x），x∈D，若存在常数C，对于任意的x1∈D，存在唯一的x2∈D，使 f(x1)+f(x2)2 =C，则称函数f（x）在D上的“均值”为C，已知f（x）=log2x，x∈[2，8]，_刷题宝

题干

定义函数y=f（x），x∈D，若存在常数C，对于任意的x₁∈D，存在唯一的x₂∈D，使

f
(
x
1
)
+
f
(
x
2
)
2

=C，则称函数f（x）在D上的“均值”为C，已知f（x）=log₂x，x∈[2，8]，则函数f（x）在[2，8]上的“均值”为（）

A：1

B：2

C：3

D：4

上一题下一题 0.0难度选择题更新时间:2019-03-28 11:38:57

答案(点此获取答案解析）

B

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