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由 大嘴 於 星期三 三月 01, 2006 6:58 pm
至少兩次是A, 即扣除一次都不是&只有一次是A:#ed_op#BR#ed_cl#=1-(1-p) ^n-p*(1-p) ^(n -1) *n#ed_op#BR#ed_cl##ed_op#BR#ed_cl#至少三次是A, 即扣除一次都不是&只有一次是A&只有兩次是A:#ed_op#BR#ed_cl#=1-(1-p) ^n-p*((1-p) ^(n -1))*n-(p^2)*((1-p) ^(n -2))*n*(n-1)/2 #ed_op#DIV#ed_cl##ed_op#/DIV#ed_cl#
[數學][問題]解答一下吧!
由 阿婆 於 星期三 十月 26, 2005 9:27 pm
Let p represent the probability of an event A. What is the probability that
1.A occurs at least twice in n independent trials
2.A occurs at least hrice in n independent trials?
請大家幫忙解答一下，非常感謝
1.A occurs at least twice in n independent trials
2.A occurs at least hrice in n independent trials?
請大家幫忙解答一下，非常感謝