The joint probability density function f(x, y) of two random variables X and Y is 0 [c(x+y) 0x y 1 mathematically described by, fxy(x, y) = otherwise Determine the value of the constant c. b) Determine the marginal probability density functions f(x) and f(y) of the random variables X and Y. c) Show that the random variables X and Y are (or are not) statistically independent. d) Determine the expected values E{X} and E{Y}, and compare the product of these two expected values with the expected value E{XY}. 2 where c is a constant. a)