(a)[3]
Set up the probability distribution table for $X$, and give the probabilities as numerical fractions.
(b)[3]
Find $\text{E}(X)$ and $\u0000\text{Var}(X)$.
Mathematics 9709 · AS & A Level · Discrete random variables
Discrete random variables — practice question
The random variable $X$ can take the values $-2, 1, 2, 3$. You are told that $P(X = x) = kx^2$, where $k$ is a constant.