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    y= x^2/ Sin^2(x) => x^2 / (Sin (x)) ^2

    Using quotient rule
    let u = x^2 v = (Sin(x))^2
    du/dx= 2x dv/dx= 2(Sin(x)) x Cos (x)= 2Sin(x)Cos(x)

    { 2x(Sin(x)^2) - 2x^2(Sin(x)Cos(x) } / Sin^4(x)

    The textbook answer is [2x{Sin(x)- xCos(x)}]/Sin^3(x)

    Im having trouble simplifying my answer further to match that of the textbook.
    PLease advise
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    (Original post by Carlos Nim)
    y= x^2/ Sin^2(x) => x^2 / (Sin (x)) ^2

    Using quotient rule
    let u = x^2 v = (Sin(x))^2
    du/dx= 2x dv/dx= 2(Sin(x)) x Cos (x)= 2Sin(x)Cos(x)

    { 2x(Sin(x)^2) - 2x^2(Sin(x)Cos(x) } / Sin^4(x)

    The textbook answer is [2x{Sin(x)- xCos(x)}]/Sin^3(x)

    Im having trouble simplifying my answer further to match that of the textbook.
    PLease advise
    Divide top and bottom by sin(x).

    Factor out 2x in the numerator.
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    (Original post by RDKGames)
    Divide top and bottom by sin(x).

    Factor out 2x in the numerator.
    Wow so simple that was.....
    Any advice on how to get better at spotting these little things ?
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    (Original post by Carlos Nim)
    Wow so simple that was.....
    Any advice on how to get better at spotting these little things ?
    Factorise whenever you can.
 
 
 
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