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Homework Help: Finding maximumx and minimums

  1. Nov 23, 2008 #1
    1. The problem statement, all variables and given/known data

    find the maxima and minima of the function f(x)=2cos3x + 3sin2x on the interval (-pie, pie)

    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Nov 23, 2008 #2
    You must show your work, before we can help you. What have you tried> Maybe something involving the derivative?
     
  4. Nov 23, 2008 #3
    im not sure if i did the derivative right. i got -2sin3x+ 3cosx as the first derivative
     
  5. Nov 23, 2008 #4

    Mark44

    Staff: Mentor

    I'm sure that you didn't. You need to use the chain rule. Your answer should start with "f'(x) = "
     
  6. Nov 24, 2008 #5
    pere callahan and mark44, is the following statement right..
    find derivative of f(x) as below
    f'(x) = -6sin(3x) + 6cos(2x)
    now solve it by equating to zero. then find critical points. from these points and end points (pie and -pie) find the absolute maxima and minima & relative maxima and minima
     
  7. Nov 24, 2008 #6
    It is.
     
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