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    Solve (2x/x+1)- (x+7/x^2-x-2) can be written in form A -B/x-2.
    Answers: A=2 B=3
    I did long division and got A is 2 but i have no idea how to get B after that, because i am left with a quadratic on top and cubic on the bottom after the long division
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    (Original post by Nirm)
    Solve (2x/x+1)- (x+7/x^2-x-2) can be written in form A-B/x-2.
    Answers: A=2 B=3
    I did long division and got A is 2 but i have no idea how to get B after that, because i am left with a quadratic on top and cubic on the bottom after the long division
    Can you post your working up to the point you get stuck?
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    (Original post by notnek)
    Can you post your working up to the point you get stuck?
    Okay so i do: 2x^3 -3x^2 -12x -7 divided by x^3 -3x -2 and end up with 2 remainder -3x^2 -6x -7. Now i have no idea what to do basically.:confused:

    ( I am doing Double)Maths is such a big jump from Gcse to A-levels
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    (Original post by Nirm)
    Okay so i do: 2x^3 -3x^2 -12x -7 divided by x^3 -3x -2 and end up with 2 remainder -3x^2 -6x -7. Now i have no idea what to do basically.:confused:

    ( I am doing Double)Maths is such a big jump from Gcse to A-levels
    You are subtracting the fractions by cross multiplying but that isn't always the most efficient way. Factorising gives

    \displaystyle \frac{2x}{x+1}- \frac{x+7}{x^2-x-2} = \frac{2x}{x+1}- \frac{x+7}{(x+1)(x-2)}

    Try subtracting them again without just cross multiplying.
 
 
 
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