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Real value of sin(i)

  1. Feb 4, 2016 #1
    I am calculating a value and want to find the real value of sin(i). I can use series expansion and only take the terms without i (correct?) but is there any nicer way to express the result of taking the real value of sin(i)?
     
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  3. Feb 4, 2016 #2

    micromass

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  4. Feb 4, 2016 #3
    I used the imaginary exponentials and found ## \sin(i) = \frac{e^{-1} - e}{2i} ## but this seems purely imaginary...from the sum expansion of sin, it appeared that there were real values for the even power terms. Any advice you have for addressing what I am missing here since I'm looking for the real value would be great!
     
  5. Feb 4, 2016 #4

    micromass

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    Indeed, ##\sin(i)## is purely imaginary. If you look at the series expansion of ##\sin(i)##, you'll see that only ##i^{\text{odd power}}## appear in this expansion. And as you know, ##i^{\text{odd power}} = \pm i##.
     
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