#How to divide a polynomial by a polynomial and a number

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azure sparrow
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how do I solve and equation where I need to divide a polynomial with a polynomial and a number (eg. (x^2 + x + 11) ÷ (x - 5))

cunning minnowBOT
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wheat goblet
# azure sparrow how do I solve and equation where I need to divide a polynomial with a polynomia...

There are several approaches. I would do it in the following way.
Notice that x^2 + x + 11 = x(x + 1) + 11. We want x - 5, however, so:
x(x + 1) + 11 = x(x - 5 + 6) + 11 = x(x - 5) + 6x + 11
So:
(x^2 + x + 11)/(x - 5) = (x(x - 5) + 6x + 11)/(x - 5) = x + (6x + 11)/(x - 5)
We then do a similar thing for 6x + 11:
6x + 11 = 6(x - 5 + 5) + 11 = 6(x - 5) + 41
So:
(x^2 + x + 11)/(x - 5) = x + (6(x - 5) + 41)/(x - 5) = x + 6 + 41/(x - 5)

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With enough practice those intermediate steps won't be necessary, and you would be able to do it like this:
(x^2 + x + 11)/(x - 5) = (x(x - 5) + 6x + 11)/(x - 5) = x + (6(x - 5) + 41)/(x - 5) = x + 6 + 41/(x - 5)

azure sparrow
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thank you!

long arrow
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there is a long division procedure too

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and a synthetic div method

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its difficult to explain by text

zinc basin
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Better to watch a video for that

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YouTube would do

azure sparrow
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ok. thank you for the information guys!

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+close