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# Ln(5x-2) ... Finding the inverse... watch

1. I know that e^ x undoes ln x but how do I find the inverse??
2. Put y=Ln(5x-2)

"e both sides", rearrange to make x the subject.
Then write the inverse function in terms of x.
3. do you mean the inverse function? as in f^-1(x)?
4. (Original post by vc94)
Put y=Ln(5x-2)

"e both sides", rearrange to make x the subject.
Then write the inverse function in terms of x.
Yh but what about the y .. Would it be y e= ln e (5x-2)
5. (Original post by sweety0471)
do you mean the inverse function? as in f^-1(x)?
Yhh..
6. e^y = e^(Ln(5x-2))
7. If you let y=ln(5x-2) and then solve this for x you will get your inverse.
If you have any trouble doing this then I am more than happy to help you further.
Note that the inverse of y=ln(x) is x=e^y.
8. (Original post by vc94)
e^y = e^(Ln(5x-2))
So the Answer would be( e^ x +2)/5
9. (Original post by Thisisj)
So the Answer would be( e^ x +2)/5

Yes, this is the inverse function!
10. might be late but

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