What Is the Limit of (2-x)/(x^2-4) as x Approaches 2?

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lim (2-x)/(x^2-4)
x>2

Find the limit(is it exists)

The substitution method failed so I factored the bottomto (x+2)(x-2).Where do I go from here?
 
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A very important but often overlooked "law of limits":

If f(x)= g(x) for all x except x= a, then \displaytype\lim_{x\to a}f(x)= \lim_{x\to a} g(x).

Here, for all x except x= 2, (2- x)/(x-2)(x+2)= -1/(x+2).
 
use l'Hospital's rule
 
Thank you
 
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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