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Homework Help: A problem in polar i want check my answer

  1. Apr 19, 2010 #1
    write in polar form ...elc
    -3 - 5i

    my answer :

    x = -3 y = - 5

    r = root (-3)^2 + (-5)^2
    = 5.83

    tan Q = 5/3 = -1.12
    tan-1 -1.12 = -0.84
    Q = -0.84
    Q = -pi + -0.84 = -3.981

    Polar form = 5.83e^(-3.981)i
     
  2. jcsd
  3. Apr 19, 2010 #2
    Ok first off:
    I believe you've recorded your answer in exponential form.

    Forms of Complex Numbers:

    [PLAIN]https://dl.dropbox.com/u/4645835/MATH/ComplexForms.gif [Broken]

    Please correct me if I'm wrong.
     
    Last edited by a moderator: May 4, 2017
  4. Apr 19, 2010 #3
    I think your angle may be wrong as well. This is what I did:

    [PLAIN]https://dl.dropbox.com/u/4645835/MATH/Ex1.gif [Broken]

    I can explain why I added 180 degrees to the angle I calculated - if needed.
     
    Last edited by a moderator: May 4, 2017
  5. Apr 19, 2010 #4
    Hi

    but as I know in this question we change calculator to ( Rad ) nor (deg) because we have integer number -3 and - 5 not roots or ,

    and please I want explaine more because I don't understand clearly
     
  6. Apr 19, 2010 #5

    Mark44

    Staff: Mentor

    tan Q = 5/3, but 5/3 is not equal to -1.12
     
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