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Homework Help: Sketching this nutty curve

  1. Feb 7, 2010 #1
    1. The problem statement, all variables and given/known data

    I need to sketch this curve from [0, pi/2]

    y = sin4xcosx

    2. Relevant equations

    3. The attempt at a solution

    I tried to generate this thing on a graphing program to see how it looked like.. otherwise I would have no idea what this is.

    Is there some easy tips to use to sketch these weird curves? Like by the derivative or something funky?
  2. jcsd
  3. Feb 7, 2010 #2


    Staff: Mentor

    Sketch y = sinx.
    Sketch y = sin4x. It's graph will be similar to the graph of y = sinx, except that no part of the graph of y = sin4x extends below the x-axis.

    On the same graph as y = sin4x, graph y = cosx. The graph of y = sin4x*cosx will be the product of the two functions. Where one function's value is zero, the product of the two will be zero. Doing this, you should get a reasonably accurate graph.
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