Integral of fraction - is this correct?

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    Fraction Integral
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Homework Help Overview

The discussion revolves around finding the integral of a rational function involving a polynomial in the numerator and a quadratic in the denominator. Participants are exploring the correctness of their individual approaches to solving the integral.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to split the fraction into simpler parts to integrate each term separately. Some participants question the validity of their calculations and seek clarification on the results obtained from an online integral calculator.

Discussion Status

There is an ongoing exploration of the integral's correctness, with some participants confirming the equivalence of different forms of the answer. The discussion reflects a mix of individual attempts and validation of results without reaching a definitive consensus.

Contextual Notes

Participants note that the text being used for reference does not provide answers, which adds to the uncertainty in verifying their solutions. The use of an online calculator is also mentioned as a point of comparison for their results.

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I am trying to find the integral of the following:

[tex]\int\left({\frac{3 + 5x - 6x^2 - 7x^3}{2x^2}}\right)dx[/tex]

What I did was to split up the fraction like so:

[tex]\int\left({\frac{3}{2x^2}}\right)dx + \int\left({\frac{5x}{2x^2}}\right)dx + \int\left({\frac{6x^2}{2x^2}}\right)dx + \int\left({\frac{7x^2}{2x^2}}\right)dx[/tex]

Simplified the fractions, worked out each integral then added them to get:

[tex]-\frac{3}{2x} + \frac{5}{2}\ln x - 3x - \frac{7}{4}x^2 + c[/tex]

The text I am using has no answers and when I tried to use the integral calculator at http://www.numberempire.com/integralcalculator.php I get an answer that is a fraction.

Am I correct and is the process I used to solve this correct?

Thanks.
 
Last edited:
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username12345 said:
I am trying to find the integral of the following:

[tex]\int({\frac{3 + 5x - 6x^2 - 7x^3}{2x^2}})dx[/tex]

The text I am using has no answers and when I tried to use the integral calculator at http://www.numberempire.com/integralcalculator.php I get an answer that is a fraction.

(use "\left(" and "\right)" for big brackets :wink:)

?? :confused:

I used that calculator and got

(10*x*log(x)-7*x^3-12*x^2-6)/(4*x)
 
tiny-tim said:
I used that calculator and got

(10*x*log(x)-7*x^3-12*x^2-6)/(4*x)

I got that too but I don't know where I went wrong with my calculation...
 
Yes, your answer is correct.

It is also equivalent to that fraction, as far as I can see.
 
Great.

And thanks for the tip on the brackets.
 

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