http://img718.imageshack.us/img718/9397/derive.png

Where did I go wrong?

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- May 1st 2010, 08:27 AMkmjtDid I derive this right?
http://img718.imageshack.us/img718/9397/derive.png

Where did I go wrong? - May 1st 2010, 08:44 AMCaptainBlack
- May 1st 2010, 08:57 AMkmjt
For somee reason I thought you can bring the denominator up and attach it, I guess you can't (Headbang)

- May 1st 2010, 09:17 AMTekken
- May 1st 2010, 09:24 AMharish21
- May 1st 2010, 09:34 AMkmjt
So far I used the quotient rule on x^2/4pi and got 8pi x / 4pi^2, is that correct?

- May 1st 2010, 09:42 AMTekken
- May 1st 2010, 09:42 AMharish21
- May 1st 2010, 09:53 AMkmjt
I think I should stick to differentiating the left and than the right, because that's what we do in class. Heres where I got my answer from doing the quotient rule on x^2 / 4pi:

f'(x) = g'(x)h(x) - g(x)h'(x) / (4pi)^2

= (2x)(4pi) - (x^2)(0) / 4pi^2

= 8pix - 0 / 4pi^2

= 8pix / 4pi^2

Where did I mess up? I used a derivative calculator online and it said the derivative would be x / 2pi

Sorry again harish thanks for that technique but I don't believe I should be doing it that way in the class im in (Happy) - May 1st 2010, 10:06 AMTekken
Ok here goes...

let and

differentiating u w.r.t x we get and

differentiating v w.r.t x we get This is always the case when differentiating constants.

Applying the quotient rule we get;

=>

=>

Now we can cancel out as it is common to both the top and bottom line.

This leaves us with - May 1st 2010, 10:06 AMskeeter
- May 1st 2010, 10:06 AMharish21
- May 1st 2010, 10:10 AMkmjt
I see thanks (Rofl)