integral (x^3 +2x^2 +3x - 2)/(x^2 +2x +2)
Hmm, this is very similar to your previous question. It would give a similar answer, it would include a log and an arctan.
I prefer here to write for you the steps that you sholud follow, and if you had a problem following the, you can ask: 1) Use long division to simplify the expression. 2) You will get this expression \(x+\frac{x-2}{x^2+2x+2}\). The first term is clear. The coming steps are about how to integrate the second term: 1) You should split it into two terms:
You know that when you split it. both of the terms you get will have the same denominator. Make the first term in manner such that the top is a multiple of the derivative of the bottom.
It doesn't matter what number you would have in the top of the other term. You will just need to write it in the form \(\frac{a}{u^2+1}\), u can be any substitution of your choice.
Or I can split it for you if you want :)
The numbers here are much better than the ones in your previous question by the way.
Since you're not saying a word, I will do it for my own entertainment -.-. \[\int\limits_{}^{}{x-2 \over x^2+2x+2}dx=\int\limits_{}^{}{x+1 \over x^2+2x+2}dx-\int\limits_{}^{}{3 \over x^2+2x+2}dx\]. For the first integral substituting \(u=x^2+2x+2 \implies du=2(x+1)dx\) yields: \[{1 \over 2}\int\limits_{}^{}{1 \over u}du={1 \over 2}\ln |u|={1 \over 2}\ln |x^2+2x+2|.\] For the second integral substitute \(u=x+1 \implies du=dx\): \[-3\int\limits_{}^{}{1 \over (x+1)^2+1}=-3\int\limits {1 \over u^2+1}du=-3\tan^{-1}u=-3\tan^{-1}|x+1|\].
for my own entertainment!
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