# Solve three algebra tasks (involving composite functions and inverse functions)

#### Math_grieg

##### New member
Given f(x) = 4x + 13, g(x) = -2x + 23. Find (f º g)(x).

Determine wether f(x) = 3x + 8 and g(x) = x - 8 / 3 are inverse functions.

For f(x) = 3x - 19, find the inverse f-¹(x). Minus sign is supposed to be uppercase..

Many thanks!!

Best,
E.G.

#### tkhunny

##### Moderator
Staff member
Why not use that composite idea to prove whether things are inverses?

Find (f(g(x)) and g(f(x)).

#### stapel

##### Super Moderator
Staff member
1. Given f(x) = 4x + 13, g(x) = -2x + 23. Find (f º g)(x).

2. Determine whether f(x) = 3x + 8 and g(x) = x - 8 / 3 are inverse functions.

3. For f(x) = 3x - 19, find the inverse f(x).

Many thanks!!
Um... you're welcome, but for what? You haven't asked a question yet!

Are you asking for lesson instruction, so you can learn what these questions mean? Are you halfway through one or another of these, and are needing help getting un-stuck? Or are you having some other difficulty?