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    \frac {x^2}{x^2 - 4}

    Divided it to give

     1 + \frac {-4}{x^2 - 4}

    Then splitting the fraction into partial fractions, I get

     \frac{1}{x+2} + \frac{-1}{x-2}

    and this does not integrate to the correct answer, which is

     x + ln¦\frac {x-2}{x+2}¦ + C

    ln bit has a modulus, but I dunno how to do that sign

    I get the x+2 on top and the x-2 on the bottom. Where have I gone wrong?
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    (Original post by lollage123)

     1 + \frac {-4}{x^2 - 4}
    This should be +4 since x^2 = (x^2-4) + 4
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    (Original post by TenOfThem)
    This should be +4 since x^2 = (x^2-4) + 4
    How? When I divide it using the polynomial division method the -4 just gets carried down and the remainder is -4/(x^2 - 4)
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    (Original post by lollage123)
    How? When I divide it using the polynomial division method the -4 just gets carried down and the remainder is -4/(x^2 - 4)
    I am not sure what you mean by "carried down"

    But, during polynomial division you would be looking at subtracting -4 which still gives +4
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    (Original post by TenOfThem)
    I am not sure what you mean by "carried down"

    But, during polynomial division you would be looking at subtracting -4 which still gives +4
    silly blunder, thank you
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    (Original post by lollage123)
    silly blunder, thank you
    np

 
 
 
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