Question

18.

For the function f(x) = x2 ­ -12, find (f o f­-1)(4).

A)4
B)10
C)6
D)0

help please?

Answer 1

f(f^-1(x)) = x by the very definition of (f o f­-1(x))

so (f o f­-1)(4) = 4