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Homework Help: Area enclosed by sine and cosine.

  1. Apr 23, 2007 #1
    1. The problem statement, all variables and given/known data

    Hello, i'm trying to find the area enclosed by sine the cosine function on the interval 45 degrees and 225 degrees, my problem is i get a negative number after i do the integration, my answer is -2 root 2.

    here's what i did,


    after integrating,


    evaluating between 45 degrees and 225 degrees,

    cos(225)+sin(225) - cos(45)-sin(45) (all of which equal -2 root 2 over 2)

    resulting in -4 root 2 over 2 or, -2 root 2
    Last edited: Apr 23, 2007
  2. jcsd
  3. Apr 23, 2007 #2
    look at the graph
  4. Apr 23, 2007 #3


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    Science Advisor
    Homework Helper

    Your signs are wrong on the integral. Eg. the integral of sin(x) is -cos(x).
  5. Apr 23, 2007 #4
    oh, darn, i was looking going in a derivative direction (now i feel like i wasted 2 hours) thanks!
    Last edited: Apr 23, 2007
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