let p(x)=(x+1)(x-3) Q(x)+a(x+1)+b where Q(X) is a polynomial and a and b are real numbers when p(x) is divided by (x+1) the remainder is -11

when p(x) is divided by (x-3) the remainder is 1

i)what it the value of b

ii)what is the remainder when p(x) is divided by (x+1)(x-3)

with working out please