# complex number calculations

Discussion in 'Math' started by suzuki, Apr 16, 2012.

1. ### suzuki Thread Starter Member

Aug 10, 2011
119
0
Hi, its been a while since i've dealt with complex numbers, so i'd like to see if anybody has some help for this problem.

say we have some complex number/expression denoted by A. (could be anything). The magnitude of A could be easily computed by

$||A|| = sqrt(AA^*)$

the problem is, i want to know how i can calculate the phase. eventually, i would like to write in the phasor form, so i would need to extract the phase somehow.

any simple solutions?

thanks

2. ### mik3 Senior Member

Feb 4, 2008
4,846
63
Say A=a+j*b

$Mag(A)=\sqrt{a^{2}+b^{2}}$

$Phase(A)=arctan(\frac{b}{a})$

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3. ### Papabravo Expert

Feb 24, 2006
10,420
1,873
On a modern calculator the "arctan" function is often represented as the inverse tangent or

$tan^{-1}(b /a)$

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