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Homework Help: Find the lowest period for the following

  1. Apr 8, 2009 #1

    so what i am looking for is the smallest x that will bring me back to my same answer, correct,,,

    now i can see that since we have a sqared function, and cos(pi)=-1, every time i reach pi, 2pi 3pi 4pi.... i will have the same answer


    is this correct?
    how do i write it in a mathematical way?
  2. jcsd
  3. Apr 8, 2009 #2


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    Homework Helper

    hi dell, if you are looking for the period of the function, it sounds about right

    maybe something write like
    [tex] f(x)=cos^2x [/tex]
    [tex] f(x) = f(x+n\pi) [/tex] [tex] ,\forall n \in \mathbb{Z} [/tex]

    you could also notice by using the properties of cos2x with the identity
    [tex] f(x)=cos^2x = \frac{1+cos2x}{2} [/tex]
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