Hi i have a question to find the inverse, and i am kinda stuck. Can anyone please help me.

Y = Srt of X + 2X

Find the inverse.

Thanks in advance =]

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- October 24th 2008, 01:24 PMferkenHelp Finding the Inverse!!!
Hi i have a question to find the inverse, and i am kinda stuck. Can anyone please help me.

Y = Srt of X + 2X

Find the inverse.

Thanks in advance =] - October 24th 2008, 01:36 PMicemanfan
Question: Find the inverse of .

The first step is to switch x and y:

Then it's time for a little equation rearrangement:

Now I'm not sure how to proceed with this, but perhaps someone else can give a little insight. - October 24th 2008, 01:39 PMferken
Thanks!

However, i actually figured it out all the way up to that part. I know the inverse is also a function, but i do not know how to figure out which answer i reject and which answer to accept. - October 24th 2008, 01:48 PMicemanfan
I think, after thinking about it, that the correct solution is . My reasoning is that the original function is always above the line , so the inverse function must always be below the line . Note that the inverse is only defined for positive values of x, because the original function, which is also defined for only positive values of x, always produces positive outputs.

- October 24th 2008, 01:57 PM11rdc11
- October 24th 2008, 02:01 PMKrizalid
Haven't you guys considered inyection and surjection? Does make sense to find the inverse?

- October 24th 2008, 02:25 PMicemanfan
This method of checking confirms that my intuition was correct. For example: (4, 10) is a point on the original function, and (10, 4) is a point on the inverse. (1, 3) is a point on the original function, and (3, 1) is a point on the inverse. Edit: 11rdc11, your proof is comprehensive and thank you.

- October 24th 2008, 02:26 PM11rdc11
Also remember that

So

is correct because

let

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