Question

Given that f(x) = x2 – 12x + 27 and g(x) = x – 9, find (f.g)(x) and express

the result in standard form.

Answer 1

Explanation:

`f(x) = {x}^(2) - 12x + 27 \\ g(x) = x - 9 \\ (f * g)(x) = ( {x}^(2) - 12x + 27)(x - 9) \\ (f * g)(x) = {x}^(3) - 9 {x}^(2) - 12 {x}^(2) + 108x + 27x - 243 \\ (f * g)(x) = {x}^(3) - 21 {x}^(2) + 135x - 243`