### Author Topic: Chapter 2.1 PG 80  (Read 1442 times)

#### Min Gyu Woo

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##### Chapter 2.1 PG 80
« on: October 16, 2018, 08:32:30 PM »
There's this little portion of text before the defining Laplace's Equation that I am confused about.

"A word of warning is merited here: Not every function $u(x,y)$ is the real part of an analytic function".

If we always define $f = u +iv$, doesn't this guarentee that $u(x,y)=\text{Re}(f)$?

#### Meiqun Lu

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##### Re: Chapter 2.1 PG 80
« Reply #1 on: October 17, 2018, 06:42:40 PM »
I think what the textbook is trying to say is that even though you could find a function f(z) whose real part can be written as u(x,y), but f(z) does not have to be analytic.