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# maths question help

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Why bother with a post grad? Are they even worth it? Have your say! 26-10-2016
1. 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

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

4. q=-15 gives you the other factor, which you can then use to easily solve the rest
5. MathMoFarah why is q 15 and not -15
6. (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

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

If (x + 1) is a factor then f(-1) = 0
7. (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
8. alright ty lol

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