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    this error involves question 10c). dy/dx=2x+3/x^2

    therefore dy/dx=2x+3(x^-2)
    x(-2)=(2*-2)+(3*(-2^-2))
    =-4+(3*-1/4)
    =-4-3/4
    =-4.75

    so the gradient when x=-2 is -4.75.....the mark scheme states it is -3.25. this value can be made by -4 + 0.75 but clearly u have to minus 0.75??? :/
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    (Original post by Rahul.S)
    this error involves question 10c). dy/dx=2x+3/x^2

    therefore dy/dx=2x+3(x^-2)
    x(-2)=(2*-2)+(3*(-2^-2))
    =-4+(3*-1/4)
    =-4-3/4
    =-4.75

    so the gradient when x=-2 is -4.75.....the mark scheme states it is -3.25. this value can be made by -4 + 0.75 but clearly u have to minus 0.75??? :/
    dy/dx 3/x^2 -> dy/dx 3(x^-2) = -6x^-3 -> -6/x^3
    x=-2 -> -6/-8 -> +3/4
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    (Original post by uninspirational)
    dy/dx 3/x^2 -> dy/dx 3(x^-2) = -6x^-3 -> -6/x^3
    x=-2 -> -6/-8 -> +3/4
    lol dw ur showin the alternate route....i understand wt i did wrong using my way cheers duo!
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    (Original post by Rahul.S)
    this error involves question 10c). dy/dx=2x+3/x^2

    therefore dy/dx=2x+3(x^-2)
    x(-2)=(2*-2)+(3*(-2^-2))
    =-4+(3*-1/4)
    =-4-3/4
    =-4.75

    so the gradient when x=-2 is -4.75.....the mark scheme states it is -3.25. this value can be made by -4 + 0.75 but clearly u have to minus 0.75??? :/
    Whats -2 x -2 ???? +4 not -4
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    (Original post by Beansontoast yum)
    Whats -2 x -2 ???? +4 not -4
    yh thts the part i got wrong....its +4 cuz the minus cancel each other out

    RIP C1
 
 
 
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