Converting Sin to Absolute Value for Multi-Variable Limits

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Homework Statement


Find the limit for x = 0 y= 0 for sin(x^2+y^2)/x^2+y^2


Homework Equations



I'm trying to use the squeeze method using the inequality |ab| <= 1/2(a^2+b^2)


The Attempt at a Solution



Is there a way I can convert sin(x^2+y^2) into absolute value |ab|

so I can get |ab| <= (1/2(x^2+y^2))/x^2+y^2


or should I use a different inequality?
 
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I don't think the approach you're attempting will do you any good. How about converting to polar coordinates? Then you're looking at the limit as r approaches zero.
 
Hi,

should I find the limit r -> 0 of sin(R^2)/R^2

= 1

regards
 
That's what it looks like to me.
 
Thanks alot!
 
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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