One of the TBD question solutions

hello everyone, I was solving this TBD question that provides three formulas which starts like this:

  1. f(x^n)=nx^(n−1)
  2. f(nx)=nf(x)
  3. f(g(x))=x^n

I have to find g(x).

I was looking at the solutions and I don’t under stand how you can use the 2nd formula to proceed with this f(x^(n+1)) = (n+1)x^n → f(x^(n+1)) / (n+1) = x^n to f(x^(n+1) / (n+1)) = x^n.

how can (n+1) go inside like that?

Hey @user2481 , I have used the reverse approach to solve this one.
f^-1 is denotation of f inverse