Question

If f(18)=12 and f is one-to-one, what is f^-1 (12)?f^-1 (12)= ?

Answer 1

Given:

f(18)=12

​f^-1 (12)=?

To find the value of f^-1(12) if f(18)=12, we use the inverse rule:

$\text{If }f\mleft(x\mright)=y,thenf^{-1}(f(x))=f^{-1}(y)=x$

Next, we let x =18 and y=12.

So if f(18)=12,f^-1(12)=18.

Therefore, the answer is:

$f^{-1}(12)=18$