COMPOSITE
FUNCTIONS
3. performs composition of functions
Definition:
• The composition of the function “f ○ g ” is defined as follows:
Examples:
Examples:
Examples:
Examples:
Examples:
Activity:
Evaluate the following composition of functions.
Given : f(x) = 2x + 1 & g(x) = 5x2
1.(𝑓 ∘ 𝑔)(𝑥)
2. (𝑔 ∘𝑓)(𝑥)
Activity:
Evaluate the following composition of functions.
Given : f(x) = 2x + 1 g(x) = 5x2
1.(𝑓 ∘ 𝑔)(𝑥)
2. (𝑔 ∘𝑓)(𝑥)
Output Presentation
Activity:
Evaluate the following composition of functions.
Given : f(x) = 2x + 1 g(x) = 5x2
1. (𝑓 ∘ 𝑔)(𝑥)
2. (𝑔 ∘𝑓)(𝑥)
Question:
How to solve composite functions?
Try these:
Evaluate the following composition of functions.
Given : 𝑓(𝑥) = 2𝑥 + 1; g(x) = 5x2 ; ℎ(𝑥) = 𝑥 + 3
1.(g ∘ h)(𝑥)
2. (f ∘ h)(𝑥)
Answer:
Evaluate the following composition of functions.
Given : 𝑓(𝑥) = 2𝑥 + 1; g(x) = 5x2 ; ℎ(𝑥) = 𝑥 + 3
1. (g ∘ h)(𝑥)
2. (f ∘ h)(𝑥)
Assignment:
Express each situation as a function of the variable being described. Let x
represent the price of a book.
1. Give a function f that represents the price of the book if a P100
price reduction applies.
2. Give a function g that represents the price of the book if a 10%
discount applies.
3. Compute (𝑓 ∘ 𝑔)(𝑥) and (𝑔 ∘ 𝑓)(𝑥). Describe what these mean.
Which of these give a better deal for the customer?

COMPOSITE FUNCTIONS.pptx