Help Evaluating integral (x^2 +2)/(x(x^2+5x+8))dx

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Homework Help Overview

The discussion revolves around evaluating the integral of the function (x^2 + 2)/(x(x^2 + 5x + 8)) with respect to x. Participants are exploring methods related to calculus, particularly integration techniques.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Some participants discuss the use of partial fractions as a method for integration. Others express frustration with the complexity of the problem and share their experiences with the integration process. There is also a mention of a potential simplification involving logarithmic integration, though its applicability is questioned.

Discussion Status

The conversation includes various attempts to evaluate the integral, with some participants confirming their results through external tools. There is an ongoing exploration of different methods, but no consensus has been reached on the simplest approach.

Contextual Notes

Participants note that the problem is situated within a calculus 2 context, which may impose certain constraints on the methods considered appropriate for solving the integral.

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Easier Way to Evaluate integral (x^2 +2)/(x(x^2+5x+8))dx

see the next post
Evaluate integral (x^2+2)/(x(x^2+5x+8)dx
 
Last edited:
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So I got the right answer and wolfram alpha confirms it

http://www.wolframalpha.com/input/?i=d%5B1%2F4ln%28|x|%29-3%2F4ln%28|sqrt%287%29%2F%282sqrt%28%28x%2B+5%2F2%29^2%2B7%2F4%29%29|%29%2B%2825sqrt%287%29%29%2F28cot^%28-1%29%28%282x%2B5%29%2Fsqrt%287%29%29%5D%2Fdx

integral (x^2+2)/(x(x^2+5x+8)dx = -3 ln| sqrt(7)/(2 sqrt( (x+ 5/2)^ 2 + 7/4) ) | + (25*sqrt(7))/7 * cot^(-1)((2x+5)/sqrt(7)) +c

and this was the integration techniques partial fractions section of the book I'm using for calculus two

that was absolutely miserable and took me forever to do
see my work is attached to see how i solved it...

how do i solve this integral in a much easier way using partial fractions what's the easiest way to evaluate this knowing that this is only calculus 2
 

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Easiest way:

[tex]\int{\frac{f'(x)}{f(x)}=ln(f(x))[/tex]
 
icystrike said:
Easiest way:

[tex]\int\frac{f\,'(x)}{f(x)}=\ln(f(x))[/tex]
How does this help?

The numerator is not the derivative of the denominator.
 

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