Suppose we have the following function:
f (x) = x
Looking for the inverse of the function we have:
y = x
Clearing x we have:
x = y
Rewriting we have the inverse is:
f ^ -1 (x) = x
Thus,
f (x) = f ^ -1 (x)
Answer:
f (x) is equal to f-1 (x) for:
f (x) = x