Question

how do i answer this question?

Answer 1

Answer:

$f^{-1}$ (59) = 20

Step-by-step explanation:

$f^{-1}$ (x) is the inverse of f(x)

to find the inverse function, let f(x) = y and rearrange to make x the subject.

y = 3x - 1 ( add 1 to both sides )

y + 1 = 3x ( divide both sides by 3 )

$\frac{y+1}{3}$ = x

change y back into terms of x with x = $f^{-1}$ (x) , then

$f^{-1}$ (x) = $\frac{x+1}{3}$ , then

$f^{-1}$ (59) = $\frac{59+1}{3}$ = $\frac{60}{3}$ = 20

Answer 2

f(x) = 3x-1
y = 3x-1
——
x = 3y - 1
y = (x+1)/3
f^-1(x) = (x+1)/3
____
f^-1(59) = (59+1)/3 = 60/3 = 20