Question

If f(x) = 12x + 7, what is f^-1(x)

Answer 1

One important thing to note
\[f^{-1} (f (x))=f(f^{-1} (x))=x\]
here we are given f(x)
\[f(x)=12x+7\]
Put \(x=f^{-1} (x)\)
We get
\[f(f^{-1} (x))= 12 \times f^{-1} (x)+7\]
so we get
\[x=12 \times f^{-1} (x)+7\]
Could you find \(f^{-1} (x)\) now?

Answer 2

In other words, y=12x+7. Switch x and y and solve for y.
x=12y+7.