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    The question asks me to find

    \int \theta \sec^2 \theta  d \theta

    Im not quite sure which bit to set as the derivative, because if i set the derivative to  \sec^2 \theta then i have to integrate sec^20 which i dont know how to do . If i tried it the other way which is to set the derivative to theta, but then it doesnt solve anything because i end up with an even more complicated integrand. Please help! rep for help.
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    Can't read it? Says 'unparseable or potentially dangerous latex formula'.
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    Without being able to read the question, sec^2 is something you should know how to integrate (by recognizing it as the derivative of something).
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    can't really help till we can see the function to integrate
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    (Original post by Clarity Incognito)
    Can't read it? Says 'unparseable or potentially dangerous latex formula'.
    Alright can you read it now?
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    (Original post by jdude22)
    The question asks me to find

    \int \theta \sec^2 \theta  d \theta

    Im not quite sure which bit to set as the derivative, because if i set the derivative to  \sec^2 \theta then i have to integrate sec^20 which i dont know how to do . If i tried it the other way which is to set the derivative to theta, but then it doesnt solve anything because i end up with an even more complicated integrand. Please help! rep for help.
    Wolframalpha (click show steps):

    http://www.wolframalpha.com/input/?i...e+x+sec^2+x+dx

    enjoy!
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    (Original post by jdude22)
    The question asks me to find

    \int \theta \sec^2 \theta  d \theta

    Im not quite sure which bit to set as the derivative, because if i set the derivative to  \sec^2 \theta then i have to integrate sec^20 which i dont know how to do . If i tried it the other way which is to set the derivative to theta, but then it doesnt solve anything because i end up with an even more complicated integrand. Please help! rep for help.
    Yeah follow Dfranklin's advice, think about what the integral of sec^2theta or conversely, what do you differentiate to get sec^2theta?
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    (Original post by jdude22)
    The question asks me to find

    \int \theta \sec^2 \theta  d \theta

    Im not quite sure which bit to set as the derivative, because if i set the derivative to  \sec^2 \theta then i have to integrate sec^20 which i dont know how to do . If i tried it the other way which is to set the derivative to theta, but then it doesnt solve anything because i end up with an even more complicated integrand. Please help! rep for help.
    If you integrate sec^2 theta you'd get tan theta. So then differentiate theta.
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    well label u as theta v' as sec^2theta and then follow it through btw, sec^2theta integrates to tantheta
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    (Original post by FinalFlash)
    If you integrate sec^2 theta you'd get tan theta. So then differentiate theta.
    Thanks, + rep
 
 
 
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