i need the derivative of :

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- Jan 24th 2010, 03:07 AMgerinikican u fin the derivative of this function
i need the derivative of :

- Jan 24th 2010, 03:11 AMtonio
- Jan 24th 2010, 03:28 AMdrumist
The solution you provided doesn't match the problem.

Can I ask what solution you arrived at? - Jan 24th 2010, 03:30 AMgeriniki
this must be solution it's in the textbook :/

sorry i haven't written it correctly = x - 1/x isn't in the power - Jan 24th 2010, 03:34 AMdrumist
Is this the correct function?

$\displaystyle f(x) = e^{1/x}\left(x-\frac{1}{x}\right)$ - Jan 24th 2010, 03:39 AMgeriniki
yes

- Jan 24th 2010, 03:51 AMdrumist
You may use the product rule:

$\displaystyle f'(x) = e^{1/x} \cdot \left(x-\frac{1}{x}\right)' + \left(e^{1/x}\right)' \cdot \left(x-\frac{1}{x}\right)$

Can you find the derivatives of $\displaystyle x-\frac{1}{x}$ and $\displaystyle e^{1/x}$? - Jan 24th 2010, 03:59 AMgeriniki
yes thank you

- Jan 24th 2010, 06:15 AMHallsofIvy
Do you see

**why**Tonio was confused? (Because he**never**gives a wrong answer!)

What you gave in your initial post was $\displaystyle e^{\frac{1}{x}\left(x- \frac{1}{x}\right)}$ not $\displaystyle e^{\frac{1}{x}}\left(x- \frac{1}{x}\right)$.