Find [tex]$f(g(x))$[/tex] and [tex]$g(f(x))$[/tex] and determine whether the pair of functions [tex][tex]$f$[/tex][/tex] and [tex]$g$[/tex] are inverses of each other.

[tex]f(x) = 5x[/tex]

[tex]g(x) = \frac{x}{5}[/tex]



Answer :

Sure, let's go through the provided mathematical functions step-by-step to answer the question.

We are given the functions:
[tex]\[ f(x) = 5x \][/tex]
[tex]\[ g(x) = \frac{x}{5} \][/tex]

### Step 1: Finding [tex]\( f(g(x)) \)[/tex]

First, let's find the composite function [tex]\( f(g(x)) \)[/tex]. This means we will substitute [tex]\( g(x) \)[/tex] into [tex]\( f(x) \)[/tex].

Given:
[tex]\[ g(x) = \frac{x}{5} \][/tex]

Substitute [tex]\( g(x) \)[/tex] into [tex]\( f(x) \)[/tex]:
[tex]\[ f(g(x)) = f\left( \frac{x}{5} \right) \][/tex]

Now apply the function [tex]\( f \)[/tex]:
[tex]\[ f\left( \frac{x}{5} \right) = 5 \left( \frac{x}{5} \right) \][/tex]

Simplify the expression:
[tex]\[ f\left( \frac{x}{5} \right) = x \][/tex]

So:
[tex]\[ f(g(x)) = x \][/tex]

### Step 2: Finding [tex]\( g(f(x)) \)[/tex]

Next, we will find the composite function [tex]\( g(f(x)) \)[/tex]. This means we will substitute [tex]\( f(x) \)[/tex] into [tex]\( g(x) \)[/tex].

Given:
[tex]\[ f(x) = 5x \][/tex]

Substitute [tex]\( f(x) \)[/tex] into [tex]\( g(x) \)[/tex]:
[tex]\[ g(f(x)) = g(5x) \][/tex]

Now apply the function [tex]\( g \)[/tex]:
[tex]\[ g(5x) = \frac{5x}{5} \][/tex]

Simplify the expression:
[tex]\[ g(5x) = x \][/tex]

So:
[tex]\[ g(f(x)) = x \][/tex]

### Step 3: Determining if [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are Inverses

To determine whether [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are inverses of each other, both of the following must be true:
[tex]\[ f(g(x)) = x \][/tex]
[tex]\[ g(f(x)) = x \][/tex]

From the calculations, we have:
[tex]\[ f(g(x)) = x \][/tex]
[tex]\[ g(f(x)) = x \][/tex]

Both conditions are satisfied.

Therefore, [tex]\( f(x) = 5x \)[/tex] and [tex]\( g(x) = \frac{x}{5} \)[/tex] are indeed inverses of each other.