Question

Help



If f(x)=2x, then f^-1(x)=

-2x
½x
x - 2

Answer 1

Switch x and y and solve for y
y=2x ==> x=2y

Answer 2

We can say f(x) is the same as y. So basically we have y = 2x. To find the inverse, switch x and y and then resolve for y. So if we switch x and y we have

x = 2y

Now all we do is solve for y, meaning divide both sides by 2 to get

y = x/2 or as you put, (1/2)x

Answer 3

Thank you guys :)

Answer 4

Mhm ^_^

Answer 5

Not surprised Psymon ;)

Answer 6

So, if you wanted to solve for
\(f(x) = 2x+3\)
\(f^{-1}(x)=?\)

Answer 7

If you wanted to do that, we would first switch x and y, meaning we would have:

x = 2y + 3

Now as above, you would now solve for y. So subtracrting both sides by 3 and then dividing by 2, we get

(x-3)/2 = y

@austinL

Answer 8

No need to teach Austin, Psymon

Answer 9

Why not? He asked, I have no reason not to answer.

Answer 10

It was directed at the asker to test their knowledge.

Answer 11

I think he was asking Jess xD

Answer 12

Well, provided he only wanted an answer, I hope he doesnt mind that I answered instead xD

Answer 13

But yeah, I am slightly past this stage in mathematics :P

Answer 14

Fair enough xD

Answer 15

Slightly? I think diff eq qualifies more than slightly

Answer 16

Haha, that, I think Diff Eqs is in another league from this xD

Answer 17

It really is a whole 'nother beast really.

Answer 18

Im in diff eq now, haha.