Answer:
[tex]f^{-1} (x) = \frac{x}{3} - 3[/tex]
Step-by-step explanation:
Let here the given function f(x) = y
or, [tex]x= f^{-1} (y)[/tex]
⇒ y = 3x+ 9
Now, solving for x, we get
3x+ 9 = y ⇒ 3x = y - 9
or, [tex]x = \frac{y-9}{3} = \frac{y}{3} - \frac{9}{3}[/tex]
⇒ [tex]x = ( \frac{y}{3}) - 3[/tex]
Now, substituting x and y
Hence, [tex]f^{-1} (x) = \frac{x}{3} - 3[/tex]
