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Homework Help: Line integral question

  1. Apr 1, 2006 #1
    http://www.mrnerdy.com/forum_img/ask.JPG [Broken]

    is the first stepc orrect?
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Apr 1, 2006 #2
    yep, everything looks good.
  4. Apr 1, 2006 #3


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    Homework Helper

    Yes, that's correct.

    But (I guess) you've used a trig identity: [itex]z'(t)=2\sin t \cos t=\sin(2t)[/itex] in the last term. This will not make your integral easier. Best leave it as [itex]2\sin t \cos t[/itex].
  5. Apr 1, 2006 #4
    thank you very much, eok and galileo!
  6. Apr 1, 2006 #5
    i get 7/6
    but when i follow galileo's advice, i get 7/3

    please help me verify again. TQ.
  7. Apr 1, 2006 #6


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    The correct answer is 7/3 but it shouldn't matter whether you use that trig identity or not.
  8. Apr 1, 2006 #7
    tq. i'll try to check back this question later.
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