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# Factor and Reminder theorem watch

1. Hi I have been stuck on how to approach this question for ages now and still don't know how to start it or if I am starting it right - I have done heard of questions with a quadratic and linear factor but never a cubic factor - Please help!!

A polynomial P(x) is the product of (x^3+ax^2-x-2) and x-b.
(a) The coefficients of x^3 and x in P(x) are zero. Find the values of a and b.

So far I have re-written P(x) given that the co-efficients of x^3 and x are 0 to be:
(-b(ax^2-2))
And then I expanded the brackets to equal:
= -abx^2 + 2b

But then I am unsure how to use this to solve for a and b and don't know if I have interpreted the question right?
2. (Original post by Glitterring)
...
Well firstly you should rewrite

in its expanded form, and then collect the coefficients of and which should be in terms of and/or . Set them equal to 0.

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Updated: January 28, 2017
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