Question

Given f(x) = 2x - 5 & g(x) = 3x + 4, find (f•g) (x)

Answer 1

Step-by-step explanation:

The notation is a little sketchy, but I think you mean f(x)*g(x), right?

We'll use the substitution property of equality. This states that for any x and y, if x = y, then we can use y in place of x, or x in place of y as needed.

Since f(x) = 2x + 5, we can replace f(x) with 2x + 5. We can also replace g(x) with 3x - 4.

To find f(x) * g(x), make the necessary replacements:

f(x) * g(x)

=(2x + 5)*(3x-4). Now FOIL it out:

=6x2 -8x + 15x - 20

=6x2 + 7x - 20.

Answer 2

Answer:

Composite of (f•g)(x) = f(g(x))

f(x) = 2x-5 and g(x) = 3x+4

(f•g)(x) = f(g(x)) = f(3x+4)

= 2(3x+4) - 5

= 6x + 8 - 5

= 6x + 3