Math Words
Mathwords: Composition
The site briefly discusses composition of functions and reviews that composition is not commutative. An example is given.
Other
Brilliant: Function Composition
Discusses the topic of function composition. Includes multiple examples and a quiz related to this topic.
Lumen Learning
Lumen: Boundless Algebra: Inverse and Composite Functions
The resource discusses the topic of function composition. Includes multiple examples and a quiz on this topic.