gjhfdfg Finding inverses to the one-to-one functions, one year ago one year ago

1. gjhfdfg

This is what I'm working on, |dw:1361136194386:dw|

2. gjhfdfg

I thought it was 7/2x-5 but I was wrong

3. poopsiedoodle

-7/-2x-5? just a guess. I'm not sure.

4. gjhfdfg

There arent any -7's in it

5. poopsiedoodle

well I know, but -7 is the opposite of 7. There aren't any -5s in it either. That looks like a +5 up there.

6. gjhfdfg

Hmm

7. gjhfdfg

I don't think it necessarily wants the opposite of everything

8. zenai

switch x and y and solve for y for the inverse of a function. $x = \frac{ 2y+5 }{ 7}$

9. Meepi

$y = \frac{2x + 5}{7}$ To get the inverse, solve for x, then swap x and y $y = \frac{2x + 5}{7}$ $7y - 5 = 2x$ $x = \frac{7y - 5}{2}$ So the inverse function is $f^{-1}(x) = \frac{7x - 5}{2}$

10. zenai

^ he's right :P

11. gjhfdfg

Got it thanks. ^^