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Explanation on how these solutions can be easily seen

  1. Apr 25, 2012 #1
    Explanation on how these solutions can be "easily" seen

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

    Show that x1(t)=cos(t) and x2(t)=sin(t) are both solutions to the following Equation.

    2. Relevant equations

    (d2x/dt2) + x = 0


    3. The attempt at a solution

    Ok, So I just cannot understand how this can easily be seen! I cannot see it at all!
    I know I haven't got any work to show you and that is wrong but I honestly do not know where to start with this.

    It is in the middle of some lecture notes and all they say is "this can easily be seen"

    Please Help this dummy!:'(
     
  2. jcsd
  3. Apr 25, 2012 #2

    Dick

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    Science Advisor
    Homework Helper

    Re: Explanation on how these solutions can be "easily" seen

    Find the second derivatives of sin(t) and cos(t). Once you do that it should be 'easily seen'.
     
  4. Apr 25, 2012 #3
    Re: Explanation on how these solutions can be "easily" seen

    Gosh now I feel super dumb :P Thanks a million!
     
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