#Help with Synthetic Division

11 messages · Page 1 of 1 (latest)

digital pollen
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I have the problem in class and can't figure it out.. Could someone break the steps down for me please?

marble fulcrum
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x^3 - 6x^2 + 11x - 6
well, you can add 0 to that
x^3 + 2x^2 - 2x^2 - 6x^2 + 11x - 6
and i did that to make the first 2 terms look like x + 2, but multiplied by something

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so x^3 + 2x^2 - 8x^2 + 11x - 6
add 0 again
x^3 + 2x^2 - 8x^2 - 16x + 16x + 11x - 6

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again, to make -8x^2 look like x + 2, it needs a -16x

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x^3 + 2x^2 - 8x^2 - 16x + 27x - 6
add 0
x^3 + 2x^2 - 8x^2 - 16x + 27x + 54 - 54 - 6
so you would finally write it as
x^3 + 2x^2 - 8x^2 - 16x + 27x + 54 - 60

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= x^2(x + 2) - 8x(x + 2) + 27(x + 2) - 60

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= (x^2 - 8x + 27)(x + 2) - 60

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this is basically long division, but like, without unnecessary symbols, imo

digital pollen
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First of all wow that was fast.. Really appreciate that!

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So you're not substituting the g(x) in the other x places?

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it just tacs onto the end?