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设随机变量ξ服从正态分布N(3,4),若P(ξ<2a-3)=P(ξ>a+2),则...
设随机变量ξ服从正态分布N(3,4),若P(ξ<2a-3)=P(ξ>a+2),则a的值为( )
A.
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B.
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C.5
D.3
考点分析:
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