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    Hi, I dont know how to solve this question at all. Please do help

    Given that -1 is a root of the equation 2x^3 - 5x^2 - 4x +3, find the two positive roots.

    The answer in the book is 1/2 and 3.
    I cant figure out how to do it please help
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    The image you attached is correct? Strictly speaking it should be "x = -1 is a root of the equation 2x^3 - 5x^2 - 4x + 3 = 0"
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    (Original post by Naika98)

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    Please don't post full solutions - it's against Forum rules
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    (Original post by Ugarit)
    Hi, I dont know how to solve this question at all. Please do help

    Given that -1 is a root of the equation 2x^3 - 5x^2 - 4x +3, find the two positive roots.

    The answer in the book is 1/2 and 3.
    I cant figure out how to do it please help
    You don't have an equation there - did you mean 2x^3 -5x^2 - 4x + 3 = 0?

    Do you know what the factor theorem tells you?

    Do you know how to do polynomial long division (or the equivalent by equating coefficients)?
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    (Original post by davros)
    Please don't post full solutions - it's against Forum rules
    Oh dear, for some reason I thought the person who posted the photo was OP silly me
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    (Original post by davros)
    You don't have an equation there - did you mean 2x^3 -5x^2 - 4x + 3 = 0?

    Do you know what the factor theorem tells you?

    Do you know how to do polynomial long division (or the equivalent by equating coefficients)?
    In the book, the '=0' isnt written.
    But Thank you so much
    I did the long division, (divided 2x^3 -5x^2 - 4x + 3 by x+1) and then factorised, and my answers were correct

    It completely slipped my mind that when they say -1 is a root of the equation, it means you can divide by x+1 with no remainder
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    Thanks for your help everyone!! Turns out all I needed to do was divide the equation by x+1 and then factorise. I feel silly for asking
 
 
 
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