Select each expression that is equivalent to 5(n + 4). A. 5n + 4
B. 5n + 20
C. 15 + 5n + 5
D. 5(n + 3) + 5
E. 5n + 54

Let x have probability generating function gx (s) and let un generating function u(s) of the sequence uo, u1, satisfies p(x > n). show that the (1- s)u(s) = 1 - gx(s), whenever the series defining these generating functions converge.