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Homework Help: Simplifying with Imaginary Numbers

  1. Mar 1, 2012 #1
    1. The problem statement, all variables and given/known data
    I'm trying to see if what I have before the e match up with the correct answer.


    the correct answer is (2+.5i)e^(1+3i)x + (2-.5i)e^(1-3i)x



    3. The attempt at a solution
    This is what I have so far.
    serqC.png

    I don't know how I would simplify anymore. Please help.
     
  2. jcsd
  3. Mar 1, 2012 #2

    jedishrfu

    Staff: Mentor

    I noticed that you rewrote sqr(-36) = 3i when it should be 6i perhaps this is where you went wrong.
     
  4. Mar 1, 2012 #3
    If you look and then divided it by 2 making it equal 3i
     
  5. Mar 1, 2012 #4

    jedishrfu

    Staff: Mentor

    sorry, didnt notice the 2 divisor.

    wrt simplifying, how about using the complex conjugate of -3+3i to multiply top and bottom that would eliminate the complex number denominator.

    Also there's eulers formula so you could convert the complex factors to e to some power and then combine the powers and simplfy further.
     
  6. Mar 1, 2012 #5
    Ok. thanks for the help. I'll try again.
     
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