Question

The domain for f(x) and g(x) is the set of all real numbers.

Let f(x) = 2x2 + x - 3 and g(x) = x + 2.
Find (f•g)(x).

2x3 + 5x2 - x-6
2x3 - 5x2 + 6
x2 - 4x + 3
2x3 - x2 + 4x - 3

Answer 1

it's the first choice: 2x^3 + 5x^2 - x - 6.

Explanation:

(f•g)(x)

= f(x) * g(x)

= (x + 2)(2x^2 + x - 3)

= 2x^3 + x^2 - 3x + 4x^2 + 2x - 6

= 2x^3 + 5x^2 - x - 6.