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Thread Subject: How do I get Real and imaginary parts of a symbolic expression?

Subject: How do I get Real and imaginary parts of a symbolic expression?

From: Emeka Obe

Date: 4 Jul, 2008 11:42:01

Message: 1 of 1

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Dear All,

I experience a problem getting the real and imaginary parts
of a complex expression in symbolic form.
For example I have this code and will like to know how to
get the real and imaginary parts:

clear; clc;
syms x y n
z=n*cos(x)+i*y*sin(x);
r = real(z);
m = imag(z);

The expressions I expected to get were:
r = n*cos(x) and
m = y*sin(x).

But I got instead :
r =

1/2*n*cos(x)+1/2*i*y*sin(x)+1/2*conj(n*cos(x)+i*y*sin(x))

and

m =

-1/2*i*(n*cos(x)+i*y*sin(x)-conj(n*cos(x)+i*y*sin(x)))

Though these are correct, I cannot I cannot simplify them
to obtain the answers I listed above. Can anyone help me
out of this?

Thanks

ES

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