Katie Pekkarinen 8.2b ECE302Fall2008sanghavi - Rhea

the variance of a binomial random variable:

var(X)

      = E[X^2] - (E[X])^2
      = E[X(X-1)] + E[X] - (E[X])^2
      = n*(n-1)*P^2 + n*p - (n*p)^2
      = n*p - n*p^2

now, set n = 1000, take derivative with respect to p, set equal to zero, solve for p, and plug into var(x) equation to solve for the maximum value.

i end up getting p = .5 so max var(X) = 250 (when X is a binomial random variable with parameter 1000)

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