Composition of Functions
https://www.aplustopper.com/composition-functions-f-o-gx/
http://cbsetuts.blogspot.in/2018/02/composition-of-functions.html
https://sites.google.com/site/aplustoppernotes/composition-of-functions
The term "composition of functions" (or "composite function") refers to the combining of functions in a manner where the output from one function becomes the input for the next function.
In math terms, the range (the y-value answers) of one function becomes the domain (the x-values) of the next function.
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