问题
单项选择题
设A、B是两个随机事件，且0＜P(A)＜1，P(B)＞0，
，则必有()。
A.A
B.B
C.C
D.D
答案
参考答案：C
解析：
由题设
知，不论A是否发生，随机事件B发生的概率相同，说明A，B互相独立。或直接用条件概率定义进行推导。
由条件概率公式及条件
于是有
可见 P(AB)=P(A)P(B)
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设A、B是两个随机事件，且0＜P(A)＜1，P(B)＞0，，则必有()。
A.A
B.B
C.C
D.D
参考答案：C
解析：
由题设知，不论A是否发生，随机事件B发生的概率相同，说明A，B互相独立。或直接用条件概率定义进行推导。
由条件概率公式及条件
于是有
可见 P(AB)=P(A)P(B)
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