Challenging Definite Integral with Square Roots and Logarithms

lordy2010
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Homework Statement



Evaluate integral from -1 to 1 of: sqrt(ln(6-x))/(sqrt(ln(6-x))+sqrt(ln(6+x)))

Homework Equations



n/a

The Attempt at a Solution



I barely know how to approach this integral. I've been trying to figure this out for a long time now, and I feel like I haven't gotten anywhere. I have even used Wolfram Alpha to take a look at the function and it looks like a straight line between -1 and 1. The answer is also, apparently, 1.

Thank you in advanced for the help!
 
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Think about using the properties of logs:

ln(xy)=ln(x)+ln(y)
ln(x/y)=ln(x)-ln(y)
 
I have considered the properties of logs and, if there were no square roots surrounding each of the ln terms, then I would have an idea of what to do. Unfortunately, there are the square roots outside of the logs so I'm still pretty lost with this integral. :-/
 
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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