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Homework Help: Opposite of a complex question

  1. Jan 25, 2010 #1
    [tex](\frac{1}{0.81e^{j0.27}})*[/tex]=[tex]\frac{1}{0.81}e^{j0.27}[/tex]
    why we can remove the constant?
    why the conjugate of a complex number is multiplication of the angle by -1
     
  2. jcsd
  3. Jan 25, 2010 #2
    Complex conjugation is distributive over multiplication, and a real number is not affected by it, therefore you can pull the constant out.

    The angle thing comes from euler's formula:

    [tex]e^{j\theta}=cos(\theta)+jsin(\theta)[/tex]

    So

    [tex](e^{j\theta})*=cos(\theta)-jsin(\theta)=cos(-\theta)+jsin(-\theta)=e^{-j\theta}[/tex]
     
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