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I Sum-difference trig identity help

  1. Jan 10, 2017 #1
    Hi,

    I am working on an engineering problem and I have an equation which takes the following form:

    x = (A * cosα * sinθ) + (B * sinα * cosθ)

    Can this be further simplified? It almost looks like one of the sum-difference formulas you find in tables of trigonometric identities. I'm not to sure about the different coeffieints though. Any help would be much apreciated.
     
  2. jcsd
  3. Jan 10, 2017 #2

    mfb

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    ##2 \cos \alpha \sin \theta = \sin(\alpha + \theta) + \sin(-\alpha+\theta)## could be interesting. Not sure if the result is "simplified", but it is at least a different compact expression.
     
  4. Jan 10, 2017 #3

    mathman

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    If |A|=|B|, he expression can be simplified.
     
  5. Jan 10, 2017 #4

    mfb

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    Staff: Mentor

    That condition is not necessary.
     
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