MEDAL AND FAN! (:
If f(x) = 2x – 7, what is the equation for f^–1(x)?

Question

MEDAL AND FAN! (:
If f(x) = 2x – 7, what is the equation for f^–1(x)?

jim_thompson5910 · Answer

Were you able to get anywhere with this one?

emilyjones284 · Answer

nope

jim_thompson5910 · Answer

alright I'll show you how to do this so you can apply it to others

emilyjones284 · Answer

okay thanks

jim_thompson5910 · Answer

Step 1) Replace f(x) with y

Step 2) Swap x and y

Step 3) Solve for y



$$\large f(x) = 2x – 7$$


$$\large y = 2x – 7$$


$$\large x = 2y – 7$$


$$\large x+7 = 2y$$


$$\large 2y = x+7$$


$$\large y = \frac{x+7}{2}$$


$$\large f^{-1}(x) = \frac{x+7}{2}$$

jim_thompson5910 · Answer

hopefully that helps and makes sense (and that you can use this on future similar problems)

emilyjones284 · Answer

That looks easy enough.. thanks because i have another problem just like that (:

jim_thompson5910 · Answer

ok great, hopefully you will know how to solve it