Find v such that f(z) = u+iv is analytic

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Homework Help Overview

The problem involves finding the function v such that f(z) = u + iv is analytic, with a focus on the Cauchy-Riemann equations and the relationship between the real and imaginary parts of the function.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the need to find v in relation to u and the application of the Cauchy-Riemann equations. There is uncertainty about the problem's clarity and whether additional information is required. Some suggest using integration to express v in terms of u, while others question the interpretation of the variables involved.

Discussion Status

The discussion is ongoing, with various interpretations being explored. Some participants have offered potential approaches to finding v, while others express confusion regarding the problem's ambiguity. There is no explicit consensus on the interpretation of the problem statement.

Contextual Notes

The original problem statement provided is minimal, leading to questions about the assumptions and information necessary to proceed with the solution.

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Homework Statement


Find v such that f(z) = u+iv is analytic.

Homework Equations


du/dx = dv/dy and dv/dx=-du/dy

The Attempt at a Solution


I'm not sure what I'm supposed to do. I think I need to find U in order to find V because if a function is analytic it satisfies the Cauchy Riemann equations. I tried to play around with cauchy riemann equations to get dv in terms of everything else but that's not helping. Can I also use the Laplace equation to solve this? This is so general that I know it's probably simple, but at the same time it makes it hard to understand what my answer is supposed to look like. What should my approach be?
 
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You can find v as function of u.
It is a bit confusing to use the same symbols for the complex components of the argument (first equation) and the complex components of the function ("relevant equations").
 
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Suppose you are given u:=u(x,y) and you know f is differentiable so it satisfies C-R, in particular,\frac{du}{dx} = \frac{dv}{dy}.
Therefore v = \int u_x dy + g(x), where u_x is the partial derivative w.r.t x. You add a function of x because when you differentiate w.r.t y, the g(x) vanishes.
 
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That's not how I would interpret the u and v given in the first post.

@Vitani11: Is that the full and exact problem statement? "Find v such that f(z) = u+iv is analytic." Nothing else given?
 
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The problem has to start from somewhere. We must either have u or v. I agree that the problem is ambiguous.
 
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That is 100% all that was given, promise. Anyway thank you I now think I can solve this.
 

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