Is U-Substitution Applicable to Integrate y/(4-y^2)^1/2?

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Homework Statement



∫ [(y)/((4-y^2)^1/2)] dy

Homework Equations


The Attempt at a Solution

 
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Did you try?
 
Please provide an attempt at a solution so we can give you tips. We can't guide you in complete void.
I will give you a tip though. Use the identity \cos^2\theta+\sin^2\theta=1.
 
Millennial said:
Please provide an attempt at a solution so we can give you tips. We can't guide you in complete void.
I will give you a tip though. Use the identity \cos^2\theta+\sin^2\theta=1.

No trig identities are necessary for this one, just the "obvious" u substitution.
 
Hi vabellabel

Welcome to PF!

According to the forum rules, you need to make an attempt first and show us your work.

Maybe rewriting the problem in the following way will help you to visualize how to find the solution of this integral:
$$\int \frac{y}{\sqrt{(4-y^2)}}\,.dy$$
Look at the denominator. To make it easier, ignore the numerator in your analysis. How would you solve that integral?
 
Since the OP showed no effort, I am locking this thread. Ordinarily our policy is to delete such posts, but owing to multiple responses, I am only locking it.
 
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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