Question

if f(x)=(2x+8)/(3x+8) find:

f^-1(-1)

f^-1(2)

Answer 1

Let f(x) = y.

In inverse function, x and y are switched to each other. Like this. f\(^{-1}\)(x) = x = (2y+8)/(3y+8) Now isolate y then plug -1 or 2 (depends on which problem you are working on) into x.

Is this clear?

Answer 2

i tried that but i kept getting the wrong answer
maybe i was calculating it wrong

Answer 3

oo i see what i did wrong
i did 2(y+8)/3(y+8)

Answer 4

Oh, there you go, lol.

Answer 5

What did you get for f\(^{-1}\)(-1)?

Answer 6

6/5?

Answer 7

it still says its wrong?

Answer 8

\[f^{-1}(x) = y = \dfrac{8x - 8}{2 - 3x}\]Is this what you get? No?

Answer 9

how did you get that?