Let X be a discrete random variable with a range of {-1, 0, +1} and P[X=-1] = a, P[X=0] = b, and P[X=+1] = a. Find the variance of X.
Added by Steven L.
Step 1
Given that X can take on the values {-1, 0, +1} with probabilities P[X=-1] = a, P[X=0] = b, and P[X=+1] = a, we can calculate the expected value as: E[X] = (-1)*P[X=-1] + 0*P[X=0] + 1*P[X=+1] E[X] = -a + 0 + a E[X] = 0 Show more…
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