Given that f(3) = 5 and f(3x) = f(x) + 3 for all x, find f^{-1}(11).
f(3) =f(3*1)=f(1)+3 = 5
so f(1)=2
f(3)=3+3 =5
f(9)=5+3=8
f(27)=8+3 =11
If f(27) = 11 then f^(-1)(11) = 27
