Is My Implicit Differentiation Method Correct?

t_n_p
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Homework Statement



http://img224.imageshack.us/img224/2459/untitledow9.jpg

Homework Equations





The Attempt at a Solution



See above picture.

I'm just curious to see if my method is correct and how exactly would I go about simplifying the answer if indeed it is correct. Thanks to anybody who can help!
 
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Your expression for the derivative of sqrt(xy) using the chain rule is in error. Y is under the square root in the expression, so the first half should be sqrt(y/x)/2. From this you should be able to get the second half.
 
Rather than writing \sqrt{xy} as (xy)1/2, write it as x1/2y1/2. I think you will find that less confusing.
 
http://img149.imageshack.us/img149/9232/workingdh2.jpg

Thanks for pointing that out, I made the relevant changes, I hope it's a bit better now. The final answer seems very, very long winded though. Am I on the right track? Hope nobody minds me posting the pictures instead, it's easier for me than doing it on the computer!
 
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Yes, you're on the right track now!
 
thanks for speed reply
My final answer is...

http://img413.imageshack.us/img413/246/finalanswml7.jpg

amiright? :-p
 
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Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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