Indefinite Integral of (3x^2-10)/(x^2-4x+4) dx using PARTIAL FRACTION

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Homework Help Overview

The discussion revolves around integrating the function (3x^2-10)/(x^2-4x+4) using partial fractions. The problem is situated within the context of calculus, specifically focusing on integration techniques and partial fraction decomposition.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the appropriate form for partial fraction decomposition, with some suggesting the use of long division due to the degrees of the numerator and denominator being equal. There are attempts to apply different forms for the decomposition, including A/(x-2) + B/(x-2)^2 and (Ax+B)/(x-2) + C/(x-2)^2. Questions arise about how to determine the correct approach and the necessity of long division.

Discussion Status

The discussion is active, with participants providing insights on the need for long division before applying partial fractions. Some guidance has been offered regarding the forms to use based on the degrees of the polynomial expressions involved. There is a recognition of the relationship between the degrees of the numerator and denominator, leading to a productive exchange of ideas.

Contextual Notes

Participants note that the problem involves integrating a rational function where the numerator's degree matches that of the denominator, prompting the need for long division before proceeding with partial fractions. There is an acknowledgment of the specific forms to consider based on the structure of the denominator.

Susie babe
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Homework Statement



Integrate (3x^2-10)/(x^2-4x+4) dx using partial fractions.


Homework Equations



None

The Attempt at a Solution



I tried using A/(x-2) + B/(x-2)^2 but I didnt get a coeffecient of an x^2.

I've also tried using (Ax+B)/(x-2) + C/(x-2)^2



Though I honestly thought that the usual A/(x-2) + B/(x-2)^2 would work, How do I know which formula to use. I know you have to do long division if the numerator has an x to a larger value than that of the denominator. I know when you have something like: (x^2-1) or (x^3+2) in the denominator then you use the Ax+B, Cx+D formula.
 
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Susie babe said:

The Attempt at a Solution



I tried using A/(x-2) + B/(x-2)^2 but I didnt get a coeffecient of an x^2.

I've also tried using (Ax+B)/(x-2) + C/(x-2)^2
Though I honestly thought that the usual A/(x-2) + B/(x-2)^2 would work, How do I know which formula to use.
The last thing that you said is correct...
\frac{A}{x - 2} + \frac{B}{(x - 2)^2}
... because the denominator is a linear factor squared. But before you try partial fractions, you have to use long division because the degrees of the numerator and denominator are the same.
 


The degree of the numerator is equal to the degree of the denominator. Try long division before partial fraction decomposition.
 


Susie babe said:

Homework Statement



Integrate (3x^2-10)/(x^2-4x+4) dx using partial fractions.


Homework Equations



None

The Attempt at a Solution



I tried using A/(x-2) + B/(x-2)^2 but I didnt get a coeffecient of an x^2.

I've also tried using (Ax+B)/(x-2) + C/(x-2)^2



Though I honestly thought that the usual A/(x-2) + B/(x-2)^2 would work, How do I know which formula to use. I know you have to do long division if the numerator has an x to a larger value than that of the denominator. I know when you have something like: (x^2-1) or (x^3+2) in the denominator then you use the Ax+B, Cx+D formula.

Re-write the numerator as
3x^2-10 = 3(x^2-4x+4)+12x - 22.
 
Ah, so if the degree of the numerator and that of the denominator are the same then you have to use long division, didnt know that. Thanks a lot guys it worked out well.
 

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