Question

nothing

Answer 1

What was your answer? What did you try?

Answer 2

let's call f(x) y and invert the varriables.

x = (2y-2)/4
4x = 2y-2
2y = 4x+2
y = (4x+2)/2

Answer 3

x=1 is not correct... see bibby's work.

Answer 4

Is that too much as far as "giving answers"?

Answer 5

Do you know how to find the inverse of a function?

Answer 6

That doesn't look right. Show your work so we can see what you're doing.

Answer 7

Do you know how to find the inverse of a function? First get the inverse of the given function.

Answer 8

Show your work...

Answer 9

Telling us you're confused doesn't help until you show us what you're trying to do.

Answer 10

You have to rearrange this equation, for x=..., then swap x and y\[\large y = \frac{ 2x-2 }{ 4 }\]
OR swap x and y now, then rearrange for y=...

Answer 11

Yep

Answer 12

\[\large x = \frac{ 2y-2 }{ 4 }\]Do you have ay idea how to rearrange this for y= ? Start by multiplying both sides by 4

Answer 13

So step through those instructions
\[y = \frac{ 2x-2 }{ 4 } -> x = \frac{ 2y-2 }{ 4 }\]
solve for y

Answer 14

what is this equal to?\[\large \frac{ x }{ 4 }*4\]

Answer 15

or this? (it's the exact same thing btw)\[\large \frac{ x }{ 4 }*\frac{ 4 }{ 1 }\]

Answer 16

No, \[\large \frac{ x }{ 4 }*\frac{ 4 }{ 1 } = \frac{ x*4 }{ 4*1 }=\]\[\large \frac{ 4x }{ 4 }\]

Answer 17

Which equals?

Answer 18

Yes

so what about this \[\large \frac{ 2y-2 }{ 4 }*4\]

Answer 19

Which one?

Answer 20

There was no equals sign...

Answer 21

so what do you get when you multiply both sides of this by 4\[\large x = \frac{ 2y-2 }{ 4 }\]

Answer 22

Are you sure?

Answer 23

Correct! :)

Answer 24

4x = 2y - 2

How you get y alone?

Answer 25

Good! Now what?

Answer 26

Wait what happened to 2y = 4x+2 ?

Answer 27

Excellent :)

Answer 28

Now it's the last step of the inverse function steps, that you posted above.

Answer 29

No, do the last step for finding an inverse function first... replace y with f^-1(x)

Answer 30

You posted the steps above for finding an inverse function...

Answer 31

Replace y with: f^-1(x). That's it.

Answer 32

It's not 8. Wait till you have the function. \[y = \frac{ 4x +2}{ 2 }\]replace y with f^-1(x)... \[\large f^{-1}(x)= \frac{ 4x +2}{ 2 }\]

Answer 33

Now you need \[\Large f^{-1}(3)\] do you know how to find it?

Answer 34

you just folved for f-1(x). treat it like any other equation

Answer 35

What would you do if you needed to find f(5) if \[\large f(x) = 2x-1\]

Answer 36

How would you find f(5)?

Answer 37

f(x) is short hand for "there is an equation with x's in it"
f(3) means "get the equation, replace all the x's with 3, and simplify"

Answer 38

f(5) means you need to plug in 5 in place of x, in the equation f(x) = 2x-1

Answer 39

in your case you have
\[ f^{-1}(x) = \frac{4x+2}{2} \]
replace the x with 3, and do the arithmetic.

Answer 40

so how can you find \[\Large f^{-1}(3) \]in this equation\[\large f^{-1}(x)= \frac{ 4x +2}{ 2 }\]

Answer 41

Right!

Answer 42

Good job :)

Answer 43

For what it's worth, in your 4 steps
****
Substitute f(x) with y. Reverse the x and y variables. Solve for y. Replace y with f^–1(x).
****
the last step is "rename" We do it to remind ourselves we found the inverse function of f(x)