The joint probability distribution of the random variables X and Y is given below:
f(x,y) = {cxy , 0 < x < 2, 0 < y < x, 0 , d.d.
a. Find the value of the constant.
b. Calculate the covariance and correlation of the random variables X and Y, and please comment.
c. Calculate the expected value and variance of the random variable Z = 2X - 3Y + 2.