Answer:
see explanation
Step-by-step explanation:
let y = f(x) and rearrange making x the subject, that is
y = 3x - 2 ( add 2 to both sides )
y + 2 = 3x ( divide both sides by 3 )
[tex]\frac{y+2}{3}[/tex] = x
change y back into terms of x with x = [tex]f^{-1}[/tex] (x)
[tex]f^{-1}[/tex] (x) = [tex]\frac{x+2}{3}[/tex]
To evaluate [tex]f^{-1}[/tex] (13) substitute x = 13 into [tex]f^{-1}[/tex] (x) , that is
[tex]f^{-1}[/tex] (13) = [tex]\frac{13+2}{3}[/tex] = [tex]\frac{15}{3}[/tex] = 5
