Looking for trustworthy answers? Westonci.ca is the ultimate Q&A platform where experts share their knowledge on various topics. Explore comprehensive solutions to your questions from knowledgeable professionals across various fields on our platform. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

MATH 1115 - SU24
Homework: Chapter 5

Question 6, 5.1.63

Part 1 of 2

Use [tex]\( f(x) = 5x - 3 \)[/tex] and [tex]\( g(x) = |x| \)[/tex] to evaluate each expression.

(a) [tex]\((f \circ g)(-3)\)[/tex]

(b) [tex]\((g \circ f)(4)\)[/tex]

---

(a) [tex]\((f \circ g)(-3) = \square\)[/tex] (Simplify your answer.)


Sagot :

Certainly! Let's solve each part step by step using the given functions [tex]\( f(x) = 5x - 3 \)[/tex] and [tex]\( g(x) = |x| \)[/tex].

### Part (a): [tex]\((f \circ g)(-3)\)[/tex]

The composition [tex]\((f \circ g)(x)\)[/tex] means we first apply [tex]\(g(x)\)[/tex], and then apply [tex]\(f\)[/tex] to the result.

1. Apply [tex]\(g(x)\)[/tex] to [tex]\(-3\)[/tex]:

The function [tex]\(g(x)\)[/tex] takes the absolute value of [tex]\(x\)[/tex].

[tex]\[ g(-3) = |-3| = 3 \][/tex]

2. Apply [tex]\(f(x)\)[/tex] to the result from [tex]\(g(-3)\)[/tex]:

Now we use the result [tex]\(3\)[/tex] from step 1 and plug it into the function [tex]\(f(x)\)[/tex].

[tex]\[ f(3) = 5 \cdot 3 - 3 \][/tex]

3. Simplify the result:

[tex]\[ f(3) = 15 - 3 = 12 \][/tex]

Therefore, [tex]\((f \circ g)(-3) = 12\)[/tex].

Answer:
[tex]\[ (f \circ g)(-3) = 12 \][/tex]

### Part (b): [tex]\((g \circ f)(4)\)[/tex]

The composition [tex]\((g \circ f)(x)\)[/tex] means we first apply [tex]\(f(x)\)[/tex], and then apply [tex]\(g\)[/tex] to the result.

1. Apply [tex]\(f(x)\)[/tex] to [tex]\(4\)[/tex]:

The function [tex]\(f(x)\)[/tex] is given by [tex]\(f(x) = 5x - 3\)[/tex].

[tex]\[ f(4) = 5 \cdot 4 - 3 \][/tex]

2. Simplify the result from [tex]\(f(4)\)[/tex]:

[tex]\[ f(4) = 20 - 3 = 17 \][/tex]

3. Apply [tex]\(g(x)\)[/tex] to the result from [tex]\(f(4)\)[/tex]:

Now we use the result [tex]\(17\)[/tex] from step 2 and plug it into the function [tex]\(g(x)\)[/tex].

[tex]\[ g(17) = |17| = 17 \][/tex]

Therefore, [tex]\((g \circ f)(4) = 17\)[/tex].

Answer:
[tex]\[ (g \circ f)(4) = 17 \][/tex]

This concludes the detailed step-by-step solution for both parts.