Suppose that a uniformly distributed random variable X can have each of the seven values
$-1, 0, 1, 2, 3, 4, 5$
and $Y = X^2-2X$
I want to get the probability mass function of Y I used the Transformation of Random Variables and got PMF of y which is $\frac{1}{7\sqrt{1+y}}$
is there another way to get PMF of y without using Transformation of Random Variables?
thanks