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Homework Help: How do I add these?

  1. Nov 27, 2007 #1
    I am stumped on how to add these together...

    y=A sin(kx+wt)


    y=A sin(kx-wt)

    any help is greatly appreciated!
  2. jcsd
  3. Nov 27, 2007 #2
    It depends on what you are trying to do with them. Are you adding them in order to simplify them to a smaller equation or are you adding them in order to graph them?
  4. Nov 27, 2007 #3
    I am actually trying to show that these are waves, and that the sum of these 2 traveling waves is the standing wave described by the equation

    y=2a {sin(kx) sin(wt)}

    The former equations are waves traveling to the right and left, respectively.

  5. Nov 27, 2007 #4
    Remember that sin(x+y)=cos(x)sin(y)+sin(x)cos(y).

    Use that on both of the different equations and add the similar figures. You should get your answer.
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