] Let p(x) = x^2 , q(x) = 2x^3 + 1, and r(x) = 7x^4 − 5x^3 − 6x − 2. Find p(q(x)) + r(x).
p(x) = x2
q(x) = 2x3 + 1
r(x) = 7x4 - 5x3 - 6x - 2
p(q(x)) = p(2x3 + 1) = (2x3 + 1)2 = 4x6 + 4x3 + 1
⇒ p(q(x)) + r(x) = 4x6 + 4x3 + 1 + 7x4 - 5x3 - 6x - 2
= 4x6 + 7x4 - x3 - 6x - 1