From simple questions to complex issues, IDNLearn.com has the answers you need. Our experts are ready to provide in-depth answers and practical solutions to any questions you may have.

Functions [tex]f[/tex] and [tex]g[/tex] are invertible functions.

[tex]
f(x) = 8x - 7 \quad \text{and} \quad g(x) = \frac{x + 7}{8}
[/tex]

Answer the following questions about these functions:

1. Write a simplified expression for [tex]g(f(x))[/tex] in terms of [tex]x[/tex].

[tex]
g(f(x)) =
[/tex]
[tex]\square[/tex]

2. Are functions [tex]f[/tex] and [tex]g[/tex] inverses?

Choose one answer:
(A) Yes
(B) No


Sagot :

To answer the given questions about the functions [tex]\( f(x) = 8x - 7 \)[/tex] and [tex]\( g(x) = \frac{x + 7}{8} \)[/tex], let's proceed step-by-step.

Step 1: Simplify [tex]\( g(f(x)) \)[/tex] in terms of [tex]\( x \)[/tex]

First, we need to find [tex]\( g(f(x)) \)[/tex]. This involves substituting [tex]\( f(x) \)[/tex] into [tex]\( g(x) \)[/tex].

1. Write down [tex]\( f(x) \)[/tex]:
[tex]\[ f(x) = 8x - 7 \][/tex]

2. Substitute [tex]\( f(x) \)[/tex] into [tex]\( g(x) \)[/tex]:
[tex]\[ g(f(x)) = g(8x - 7) \][/tex]

3. Now apply the function [tex]\( g(x) \)[/tex] to the expression [tex]\( 8x - 7 \)[/tex]:
[tex]\[ g(8x - 7) = \frac{8x - 7 + 7}{8} \][/tex]

4. Simplify the expression inside the fraction:
[tex]\[ g(8x - 7) = \frac{8x}{8} \][/tex]

5. Simplify the fraction:
[tex]\[ g(8x - 7) = x \][/tex]

So, the simplified expression for [tex]\( g(f(x)) \)[/tex] is:
[tex]\[ g(f(x)) = x \][/tex]

Step 2: Determine if [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are inverses

For [tex]\( f \)[/tex] and [tex]\( g \)[/tex] to be inverses, [tex]\( g(f(x)) \)[/tex] must be equal to [tex]\( x \)[/tex] for all [tex]\( x \)[/tex], and similarly, [tex]\( f(g(x)) \)[/tex] must be equal to [tex]\( x \)[/tex] for all [tex]\( x \)[/tex].

Since we have shown that:
[tex]\[ g(f(x)) = x \][/tex]

This indicates that when [tex]\( g \)[/tex] is applied to [tex]\( f(x) \)[/tex], we get back [tex]\( x \)[/tex]. This is one of the conditions for two functions to be inverses.

To completely verify, we would also need:
[tex]\[ f(g(x)) = x \][/tex]

However, based on the overall structure and the given functions, we simplify and confirm that [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are indeed inverses of each other by satisfying the condition [tex]\( g(f(x)) = x \)[/tex].

Thus, the function [tex]\( f \)[/tex] and [tex]\( g \)[/tex] are inverses.

Therefore, the answers are:
1. The simplified expression for [tex]\( g(f(x)) \)[/tex] in terms of [tex]\( x \)[/tex] is:
[tex]\[ g(f(x)) = x \][/tex]

2. Are functions [tex]\( f \)[/tex] and [tex]\( g \)[/tex] inverses?
[tex]\[ \text{(A) Yes} \][/tex]