(New page: Use the binomial theorem to expand the expression (x+y)^n+(x-Y)^n you will find out that only the terms with even n remains. Then you relate this model to the problem by substituting x,y w...) |
m (4.2b Junzhe Geng moved to 4.1b Junzhe Geng: Improperly named originally) |
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Latest revision as of 06:43, 15 October 2008
Use the binomial theorem to expand the expression (x+y)^n+(x-Y)^n you will find out that only the terms with even n remains. Then you relate this model to the problem by substituting x,y with p, 1-p and you will find out that the right hand side(the expanded terms) is 2 times P(X is even), so you can solve it.
