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Math Help - trig integral

  1. #1
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    Question trig integral

    integral
    dx/[(sin x)(cos x)]

    how do i approach such an example
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  2. #2
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    Quote Originally Posted by alex83 View Post
    integral
    dx/[(sin x)(cos x)]

    how do i approach such an example
    \frac{1}{\sin x \cos x} = \frac{2}{\sin 2x} = 2 \csc 2x and

    2 \int \csc 2x\, dx is a standard integral (if u = 2x).
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  3. #3
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    alex83 - Once again I'm going to ask that you show some effort before making another thread on trig integral problems. It seems you are going down the list of your homework. We want you to learn how to do these on your own and it doesn't seem you know how to.
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  4. #4
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    Quote Originally Posted by alex83 View Post
    integral
    dx/[(sin x)(cos x)]

    how do i approach such an example
    sin x cos x can be re-written as 0.5 sin (2x). So your job is to integrate a cosec function. See here: http://www.mathhelpforum.com/math-he...barrassed.html

    You will not get any further help on this question until you show your working and state where you get stuck. You may not think so, but this is actually for your own academic benefit. Maths is not a spectator sport.
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  5. #5
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    Quote Originally Posted by Jameson View Post
    alex83 - Once again I'm going to ask that you show some effort before making another thread on trig integral problems. It seems you are going down the list of your homework. We want you to learn how to do these on your own and it doesn't seem you know how to.
    actually im studying for my finals and i have my solution manual with me but when the book shows an answer differnet than mine and i dont understand the way they got to a certain step i seek help from this helpful forum which i learned from more than my class..

    thank you anyway but pls. dont get me wrong
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  6. #6
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    Quote Originally Posted by alex83 View Post
    actually im studying for my finals and i have my solution manual with me but when the book shows an answer differnet than mine and i dont understand the way they got to a certain step i seek help from this helpful forum which i learned from more than my class..

    thank you anyway but pls. dont get me wrong
    If that happens you should post the solution you've been given and say what part of it you don't understand.
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