## anonymous one year ago What is the inverse of f(x) = 2x − 8?

1. anonymous

To find the inverse of a function you are first gonna need to replace f(x) with y. Then you have to flip the x and y variables and solve for y. @sherlocked1270

2. rishavraj
3. anonymous

f(x) = 2x − 8 y = 2x − 8 x = 2y − 8 x+8=2y and so on..

4. anonymous

wait so what do I do after I get to x=2y+1

5. anonymous

you solve for y 2y=x-1 y=(x-1)/2

6. UsukiDoll

$$\color{blue}{\text{Originally Posted by}}$$ @sunleaf01 f(x) = 2x − 8 y = 2x − 8 x = 2y − 8 x+8=2y and so on.. $$\color{blue}{\text{End of Quote}}$$ After this step we are supposed to divide 2 throughout the equation.

7. anonymous

can someone help me with my question http://openstudy.com/updates/55a65b2be4b0f93dd7c4162d

8. anonymous

how do I remove the parentheses from Y=(x-1)/2

9. rishavraj

how did u get tht??? y = 2x + 8 switch x and y x = 2y + 8 x - 8 = y x/2 - 4 = y now stick inverse notation

10. UsukiDoll

there's an error. Everything is fine until x+8=2y divide 2 throughout the entire equation to have y by itself the fraction part is correct, but we should have a 4

11. anonymous

ok I'm going on break see u later

12. rishavraj

u will get x - 8 = 2y so (x - 8)/2 = y x/2 - 8/2 = y x/2 - 4 = y

13. anonymous

@rishavraj i ony saw sherlocked questin with x=2y+1 haha my bad i didnt see ur guys responses

14. UsukiDoll

that's alright. mistakes do happen ^^

15. anonymous

and can anyone help with this http://openstudy.com/updates/55a65b2be4b0f93dd7c4162d

16. anonymous

so u were saying that you have to get rid of the F(x) but in the answers that are provided It has f(x) f^-1(x)=1/2x-8 f^-1(x)=1/2x+4 f^-1(x)=1/2+8 f^-1(x)=2x+16

17. anonymous

hey

18. anonymous

hi

19. rishavraj

see my just previous reply... i ended with y = x/2 + 4 replace y from f^-1(x) so it woud be f^-1(x) = x/2 + 4

20. anonymous

oh ok thank u :D

21. rishavraj

u welcome :))))

22. anonymous

ans is x+8 ------- 2