下列判断错误的是{"A":"\u82e5\u968f\u673a\u53d8\u91cf\u03be\u670d\u4ece\u6b63\u6001\u5206\u5e03N\uff081\uff0c\u03c32\_刷题宝

题干

下列判断错误的是（）

A：若随机变量ξ服从正态分布N（1，σ²），P（ξ≤4）=0.79，则P（ξ≤﹣2）=0.21

B：若n组数据（x₁，y₁）…（x_n，y_n）的散点都在y=﹣2x+1上，则相关系数r=﹣1

C：若随机变量ξ服从二项分布：ξ～B（5， $\frac{1}{5}$ ），则Eξ=1

D：“am²＜bm²”是“a＜b”的必要不充分条件

上一题下一题 0.0难度选择题更新时间:2015-08-26 06:09:10

答案(点此获取答案解析）

D

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