I know the E(I[sub:92pwfhv3]A[/sub:92pwfhv3]) = P(A), but I don't know how you would use this to find the distribution.

Is the expectation simply P(A)[sup:92pwfhv3]2[/sup:92pwfhv3] + 2*P(A)*P(B) + P(B)[sup:92pwfhv3]2[/sup:92pwfhv3]?

b) Suppose that X is a random variable with just two possible values a and b. For x = a and b find a formula for p(x) = P(X = x) in terms of a, b and mu = E(X).

Thanks for any help!