Complex numbers - hurwitz theorem

hermanni
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Hi all,
I'm trying to solve this question , can anyone help??
Suppose that D is an open connected set , fn ->f uniformly on compact subsets of D. If f is nonconstant and z in D , then there exists N and a sequence zn-> z such that
fn ( zn ) = f(z) for all n > N.

hint: assume that f(z) = 0. Apply Hurwitz theorem to in disk D(z0 , rj ) for a suitable sequence of rj -> 0

I reallt don't have an idea and I don't understand how to use hint.Can anyone give a hint??
 
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Do you understand what Hurwitz's theorem tells you in this context?
 
Actually I didn't . The theorem says fn and f have the same number of zeroes, I don't understand how we supposed to use 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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