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Math Help - Roots of a cubic equation

  1. #1
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    Roots of a cubic equation

    Right The First Question Is :

    1. Given that x=-2 and x=1 are two root of the equation x3+px2-6x+q=0, establish the values of p and q and hence find the third root of the equation

    Can Someone Please Show Me How To Do It ... Would Be Much Appreciated x
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  2. #2
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    expand (x+2)(x-1)(x+a) and equate coefficents to x^3+px^2-6x+q
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