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    g(x)=x^3+px^2-13x+q
    given that (x+1) and (x-3) are factors of g(x)

    a) show that p=3 and find the value of q
    b) solve the equation g(x)=0

    thanks in advance.
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    What have you tried?
    Where is the rest of the question?
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    sorry lol just included the rest, and ive tried this:

    Name:  maths q sr.png
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    q=-15 gives you the other factor, which you can then use to easily solve the rest
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    MathMoFarah why is q 15 and not -15
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    (Original post by DeCosta)
    g(x)=x^3+px^2-13x+q
    given that (x+1) and (x-3) are factors of g(x)

    a) show that p=3 and find the value of q
    b) solve the equation g(x)=0

    thanks in advance.
    It's much easier to to use the factor theorem rather than divide.

    If (x + 1) is a factor then f(-1) = 0
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    (Original post by DeCosta)
    MathMoFarah why is q 15 and not -15
    I just copied down what you wrote without checking too carefully, it is -15
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    alright ty lol
 
 
 
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