This deep dive covers Method: Finding Composite Functions within Composite Functions for GCSE Mathematics. Revise Composite Functions in Algebra for GCSE Mathematics with 14 exam-style questions and 12 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 3 of 8 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Method: Finding Composite Functions
1Identify which function to do first (inner function)
2Substitute the first function into the second
3Simplify the expression
4Check your answer by substituting values
Practice questions for Composite Functions
The composite function fg(x) means: A) Apply g first, then apply f to the result B) Apply f first, then apply g to the result C) Multiply f(x) by g(x) D) Add f(x) to g(x)
Explain why, in general, fg(x) and gf(x) are NOT equal. You may use an example to support your explanation.
Quick recall flashcards
What does fg(x) mean?
fg(x) = f(g(x)): apply g first (inner function), then apply f to the result.
Do the function closest to x first.
What is a composite function?
A function formed by chaining two functions together.
The output of one function becomes the input of the next.