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Homework Help: Average value

  1. May 14, 2008 #1
    1. The problem statement, all variables and given/known data

    find the average value of cos^2(x) [0,(pi/4)]

    2. Relevant equations

    I don't think i'm doing it correctly I know the formula,(I won't put my attempt because I don't have math symbols on my computer) but I get 1 as the answer every time which doesn't seem correct

    3. The attempt at a solution
  2. jcsd
  3. May 14, 2008 #2


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    Gold Member

    You should try to give your attempt.
    If you select "Go Advanced" during a Quick Reply
    or "Quote" an earlier post, you'll see a small [tex]\Sigma[/tex] symbol, which will help you compose the mathematical symbols.
  4. May 14, 2008 #3
    ok so my attempt is


  5. May 14, 2008 #4
    hmm im sorry im new i don't think i can get it right the 4/pi is the upper bound the 0 is the lower bound
  6. May 14, 2008 #5


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    Don't worry about the formatting. Better luck next time. But you are doing great! Except (2/pi)[pi/4+(1/2)] doesn't equal 1. Notice where I put the brackets.
    Last edited: May 14, 2008
  7. May 14, 2008 #6
    Soo that would be equal to
  8. May 14, 2008 #7


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    Yessss. It would. That's 0.8183... Not 1.
  9. May 14, 2008 #8
    thank you so much
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