The function f(x)= ax+b , f-1(x)=8x-3. Find a and b

I would be very happy if you explained how to do it.

Thank you

Printable View

- October 27th 2009, 10:12 AMOasis1993Inverse funciton
The function f(x)= ax+b , f-1(x)=8x-3. Find a and b

I would be very happy if you explained how to do it.

Thank you - October 27th 2009, 10:25 AMramiee2010
- October 27th 2009, 12:30 PMOasis1993
Thank you very much!

- October 28th 2009, 08:52 AMHallsofIvy
Just to put in my oar: 8x- 3 says "first multiply x by 8 and then subtract 3".

The "inverse" is the inverse of the original operarations ("divide by 8" rather than "multiply by 8" and "add 3" rather than "subtract 3") done in the**opposite**order.

So the inverse of "first multiply x by 8 and then subtract 3" is "first add 3 to x and then divide by 8".