How to Simplify an Integrand by Dividing the Denominator into the Numerator?

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SUMMARY

The discussion focuses on simplifying the integral \(\int \frac{8x^{3}dx}{4x^{2}+4x+5}\) by dividing the denominator into the numerator. The solution involves polynomial long division, which transforms the integral into \(\int 2x-2-\frac{2x-10}{4x^{2}+4x+5}\). The user initially struggled with the concept but received guidance on using polynomial long division to achieve the simplification. This method is essential for handling integrals where the degree of the numerator exceeds that of the denominator.

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Students beginning their studies in calculus, particularly those learning integration techniques, as well as educators looking for clear explanations of polynomial long division in the context of integrals.

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I've just started fundamental Integration, so I don't know too many tricks, and every once and a while my textbook does something that I can't follow. In this case, it's not in the actual solving of the integral so much as it simplifying the function. Here's the problem:

\int \ \frac{8x^{3}dx}{4x^{2}+4x+5}

In my textbook, it says "We can rewrite the given integral by dividing the denominator of the integrand into the numerator. Doing this, we obtain:"

\int \ 2x-2-\frac{2x-10}{4x^{2}+4x+5}

I have absolutely no idea how to do that. I thought I might be able to pull it off with long division or synthetic division, but I don't really know how to do it. I tried doing a quick google to find out what to do, but it's all division with a single root. I'm sure it's actually really simple, but I just can't figure it out.

Sorry if this is in the wrong section. I figured because it was in the middle of solving a Calculus problem, this was the forum to put it in. Thanks in advance!
 
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Use polynomial long division (quickie tutorial in that http://www.mathsrevision.net/alevel/pages.php?page=1.)
 
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I knew it was something simple that I was missing...

Thanks a bunch, benorin. Now I can finish up that problem and turn in for the night!
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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