Finding a new function given a composite function (Case B : Second function is given) Example 1

Posted on April 18, 2020 by user

Example 1 (substitution Method)
A function f is defined by

f : x \mapsto x + 2

.
Find the function g if

g f : x \mapsto x^{2} + 3 x + 5

.

[Note : Second function is given, use substitution y = x + 2]