原帖由 liuyaoerxia 于 2007-10-8 08:41 PM 发表
P(A+B+C)-P(A+B)
=P(A)+P(B)+P(C)-P(AB)-P(AC)-P(BC)+P(ABC)-P(A)-P(B)+P(AB)
=P(C)-P(AC)-P(BC)+P(ABC)
=P(A非C)-[P(BC)-P(ABC)]
=P(A非C)-P(A非BC)
=P(A非B非C)
不好意思,A的对立事情不会打,只能这样,看 ...
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