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    I have tried this sum 3-4 times and its impossible!!! Someone help me asap !!

    Use the substitution x=sec(theta) and integration to find the value of


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    Answer= 0.0940
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    have u used the identity sec^2x =1 tan^2x
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    (Original post by whizz-kid)
    have u used the identity sec^2x =1 tan^2x
    U mean sec^2x= 1+tan^2x ? Why do you need that here? Cant you just integrate Sec^2x directly?
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    (Original post by warkan)
    U mean sec^2x= 1+tan^2x ? Why do you need that here? Cant you just integrate Sec^2x directly?
    No when you make the substitution x=sec u, then the x^2-1 becomes sec^2 u-1=tan^2 u. We then need to find dx in terms of du. Differentiating x=sec u gives us dx=secutanu du. Make this substitution and remember to change the limits
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    (Original post by warkan)
    U mean sec^2x= 1+tan^2x ? Why do you need that here? Cant you just integrate Sec^2x directly?
    if you were just integrating sec^2(x) then yes, but you're not.

    How about you make the substitution (using integration by substitution) and see what it looks like, then use the identity sec^2(x)-1 = tan^2(x).
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    (Original post by JoMo1)
    if you were just integrating sec^2(x) then yes, but you're not.

    How about you make the substitution (using integration by substitution) and see what it looks like, then use the identity sec^2(x)-1 = tan^2(x).
    your sig is funny.
 
 
 
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