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Homework Help: Complex numbers

  1. Apr 2, 2005 #1
    Hello, I have this complex number that I need to convert to polar coord represntation:
    z = 1 + j;
    the answer is sqrt(2)e^-j45
    (45 is degrees).
    The part I don't undestand is negative before j45, since a and b are positive, I assumed it's in the first quandrant of Im/Re plane, and if the reference point for theta is real axis postive direction I do not see why there is a "-".
    Thanks for explanation.
     
  2. jcsd
  3. Apr 2, 2005 #2

    dextercioby

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    I'm sure it's a mistake.It should be

    [tex]1+j=\sqrt{2}e^{+j\frac{\pi}{4}} [/tex]

    Daniel.
     
  4. Apr 2, 2005 #3
    Thanks, that makes me happier :smile:
    But generally, the "-/+" of the angle depends on the position of a and b in the im/real plane, so theta is counted from positive direction of real axis, like usually in geometry ... is it right?

    Thank you again.
     
  5. Apr 2, 2005 #4

    dextercioby

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    Yes.Theta/the angle is anticlockwise.

    Daniel.
     
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