#How to divide a polynomial by a polynomial and a number
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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)
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)
thank you!