Question

Can you also give a function that is the inverse of itself?

Answer 1

f(x)=x

Answer 2

It's the only one I believe.

Answer 3

f(x) = 1/x

Answer 4

f(x)=1/x

Answer 5

nice, didn't think of that.

Answer 6

Actually there are infinitely many, here's a fun one: f(x)=x+1 if x is odd, f(x)=x-1 if x is even. with x a natural number.

Answer 7

f^-1(f(x) = x Inverse
f(f(x) = x Self-inverse