Branch points [Complex Analysis]

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The function f(z) = (z^2 + 1 + i)^(1/4) is a multi-valued function with branch points determined by the roots of the expression inside the parentheses. The discussion highlights that there are two solutions for z when f(z) is set to zero, specifically at z = sqrt(-1 - i) and z = -sqrt(-1 - i). To create a continuous branch in the cut-plane, a specific choice of branch cuts is necessary, although the exact cuts are not detailed in the discussion. Additionally, different branch cuts can yield alternative examples of continuous branches for the function. Understanding the implications of these branch points and cuts is crucial for analyzing the behavior of multi-valued functions in 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
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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