Question

f : R $\times$ r, be defined by $f\left(x\right)=3x-5.$ The formula that defines the reverse $f^n{f}^{-1}$ is

• A. $3y-5$
• B. $5-3y$
• C. $\frac{y+5}{3}$
• D. none

Answer 1

The correct option is C $\frac{y+5}{3}$

$f\left(x\right)=3x-5$

Let $f\left(x\right)=y$, $x=f^{-1}\left(y\right)$

$y=3x-5$

$x=\frac{y+5}{3}$

$f^{-1}\left(y\right)=\frac{y+5}{3}$.