Limit question (from complex analysis)

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Homework Statement



This seems to be just a simple limit problem and I feel like I should know it but I'm just not seeing it.

I have a continuous function f, and a fixed w

I want to show that the limit (as h goes to 0) of the absolute value of:

(1/h)*integral[ f(z)-f(w) ]dz = 0 (the integral is over a contour)


Homework Equations



I believe the key to the problem is that f is continuous.

The Attempt at a Solution



For any a>0 there exists a b>0 such that z within b of w implies f(z) within a of f(w).

The problem is it seems to me like the 1/h term is going to infinity while the integral term is going to 0, which is indeterminate so I don't know how to get that the limit goes to 0.
 
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Oh, I have an idea. The contour I'm integrating over is the line connecting w+h to w. So I believe I can use the ML Estimate to show the limit goes to 0...
 
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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