Question

Find the variance when E(x)= -4.5

Answer 1

according to my textbook:

if X is a random variable on a sample space S and E(X) = \(\mu\), then

V(X) = E((X-\(\mu\))^2)

Answer 2

or from a previous thrm stated in the text:

V(x) = E(x^2)-E(x)^2