Branch points [Complex Analysis]

machofan
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Homework Statement


Hi, I'm stuck with this question:
How many branches (solutions) and branch points does the function
f(z) = (z2 +1 +i)1=4 have? Give an example of a branch of the multi-
valued function f that is continuous in the cut-plane, for some choice
of branch cut(s). Now by choosing different branch cut(s), provide a
different example.

Homework Equations


f(z) = (z2 +1 +i)1=4

The Attempt at a Solution


So I've done the first part, by setting f(z) = 0 then solving for two solutions of z to be sqrt(-1-i) and z= -sqrt(-1-i), but I'm not sure how to proceed onto the next part of the question. [/B]
 
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machofan said:
(z2 +1 +i)1
What does that expression mean? It looks like maybe z2+1+i, but what is the final 1 doing?
 
Woops sorry! The function z is meant to say (z^2+1+i)^1/4
 
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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