Hi Math help forum!

I'm finding it difficult to differentiation from first principals and wanted to know if there is a simple method I can follow. Could you please give an example aswell thanks.

regards

dadon

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- May 9th 2006, 01:54 AMdadondifferentiation from first principals
Hi Math help forum!

I'm finding it difficult to differentiation from first principals and wanted to know if there is a simple method I can follow. Could you please give an example aswell thanks.

regards

dadon - May 9th 2006, 07:40 AMTD!
"from first principles" would be using the (limit) definition?

- May 9th 2006, 09:33 AMdadon
Thanks for the reply

Yes any method as long as it easy to follow and you get the right answer! :D - May 9th 2006, 09:36 AMTD!
Well there is no standard 'way' of doing them, since evaluating limits can go very different, depending on what limit it is. For what kind of functions do you have to be able to get its derivative through the definition?

- May 9th 2006, 11:28 AMJameson
Just so I'm clear, is this what you are talking about?

$\displaystyle f'(x)=\lim_{\Delta{x}\rightarrow{0}}\frac{f({x}{+} \Delta{x})-f(x)}{\Delta{x}}$? - May 9th 2006, 02:03 PMThePerfectHacker
I realized that you used

Code:`\rightarrow`

Code:`\to`

- May 9th 2006, 02:46 PMdadon
yeah jameson when the limit turns zero.

- May 9th 2006, 05:50 PMJamesonQuote:

Originally Posted by**dadon**

- May 9th 2006, 05:51 PMJameson
PerfectHacker:

Thanks. A small time saver. :) - May 9th 2006, 06:40 PMThePerfectHackerQuote:

Originally Posted by**Jameson**

- May 10th 2006, 01:02 AMdadonre:
So say I had to find from first principals $\displaystyle \frac{dy}{dx}$ of the following:

$\displaystyle y = 16x + \frac{1}{x^2}$

cheers guys - May 10th 2006, 09:16 AMJameson
Set up your limit.

$\displaystyle \frac{dy}{dx}=\lim_{\Delta{x}\to{0}}\frac{16(x{+}{ \Delta}x)+\frac{1}{(x{+}{\Delta}{x})^2}-16x-\frac{1}{x^2}}{\Delta{x}}$

Is this where you're having trouble? - May 10th 2006, 09:17 AMdadon
thanks for the reply.

yes that is what i needed help on. - May 10th 2006, 01:59 PMThePerfectHackerQuote:

Originally Posted by**dadon**