from finding the inverse function evaluating function and op
from finding the inverse function, evaluating function and operation with functions, Does the order of composition matters?
Solution
Short answer: Yes it does.
 
 Here is an example.
 
 f(x) = 3x
 g(x) = x2
 
 (fog)(x)=f(x2)=3*(x2)=3x2
 (gof)(x)=g(3x)=(3x)2=9x2
 
 I haven\'t proven this vigorously, but I conjecture that there are more examples where the order matters than when it doesn\'t.

