Expected values and probability mass function.

Hi everyone. I am incredibly lost on this problem and I have no idea how to do it. It seems like it's easy, but I'm just not getting it. Any hints would be extremely helpful. Thanks!

Let X be a random variable taking values 0, 1 or 2. Suppose E[X] = m_1

and E[X^2] = m_2. Compute P [X = i] for i = 0; 1; 2.

(E is expected value; P is the probability function.)

Re: incredibly lost... please help... probability mass functions

Re: incredibly lost... please help... probability mass functions