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Homework Help: Integral of x^2 sin pi x

  1. Sep 9, 2010 #1
    My calc is a bit rusty & i can not solve this problem for the life of me.
    its the integral of x^2sin pi x.
    I know you must integrate by parts..& i am have tried using both x^2 and sin pi x as my u.
    Any help?
    time is of the essence.

    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Sep 9, 2010 #2

    vela

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    You have to integrate by parts twice. The trig part doesn't go away, but the polynomial part will go down in degree every time you differentiate it until you're just left with the integral of sin x.
     
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