Composition of two functions: Basic

Question

Suppose that the functions p and q are defined as follows.

p(x) = −3x + 1

q(x) =−5x - 1



Find the following.

(p times q)(-4) = ?

(q times p)(-4) = ?

Answer 1

(-3x+1)(-5x-1) =15x-2x -1 use the FOIL method

-4pq = -4qp = -4(15x-2x-1) = -60x+8x +4

unless you probably meant

pq(-4) as p(-4)q(-4)

= 15(-4) -2(-4) -1 = -60+8-1 = -53

I'd go with pq(-4) = qp(-4) = -53