Is there an easier way to solve rational equations?

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Discussion Overview

The discussion revolves around the methods for solving rational equations, particularly focusing on whether there are easier alternatives to the traditional approach of factoring polynomial equations derived from rational expressions. Participants explore various techniques and express their frustrations with the standard methods.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant expresses a desire for a simpler method to solve rational equations beyond factoring, suggesting the possibility of using integration or derivation.
  • Another participant describes the standard approach of multiplying by the least common denominator to convert to a polynomial equation, emphasizing that solving the polynomial often involves factoring or using the quadratic formula.
  • A participant acknowledges the traditional method but reiterates the search for a quicker solution, indicating a shared frustration with the process.
  • One participant argues that having the polynomial in factored form is more convenient than as a sum of terms, suggesting that this is the most efficient way to handle polynomials in the denominator.
  • Another participant speculates that while formulas could potentially be developed for specific classes of rational equations, they may not necessarily simplify the solving process.
  • A later reply introduces the idea of using multiple Newton iterations followed by polynomial deflation, although it notes the potential complexity of the resulting fractions.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the existence of a simpler method for solving rational equations. There are multiple competing views on the effectiveness and convenience of various approaches, with some expressing skepticism about finding easier solutions.

Contextual Notes

Participants discuss the limitations of existing methods, including the complexity of higher-degree polynomial equations and the challenges associated with finding simpler solutions. There is an acknowledgment of the difficulty in developing universal formulas for rational equations.

cmcraes
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Hi there, I've been learning about Solving for x in rational expressions with Mono, Bi and tri nomial denominators, and I was curious if there was an easier way to solve them than by factoring.

I already understand and fully grasp the concept, but its just annoying to go through all the same steps over and over again.

Is there some process (maybe integration, or derivation) that could 'simplify' the problem? Thanks!
 
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You multiply on both sides of the equations by the "least common denominator" to convert to a polynomial equation. Then you have to solve the polynomial equation- and one way of doing that is factoring! I presume you know the "quadratic formula". There also exist formulas (though much more difficult http://www.sosmath.com/algebra/factor/fac11/fac11.html, http://www.sosmath.com/algebra/factor/fac12/fac12.html). There do not, and can not, exist formula that solve higher degree polynomial equations (in terms of elementary functions such are roots).
 
Yes i know you can turn it into a Polynomial equation and factor it, Thats exactly what I am trying to find a quicker way of doing! Haah
 
I don't think there is a quicker way. When there is a polynomial in the denominator, it's much more convenient to have the polynomial in factored form (as a product of lower-degree polynomials) than it is to have it as a sum of terms.
 
I wouldn't be surprised if you could come up with a formula for a few certain classes of rational equations (like you can for quadratic, cubic, quartic), but it would not necessarily be any easier to solve. It might be fun to find some... but I'm not going to do it.
 
I would run multiple Newton iterations then deflate the polynomial.

Tough luck if what comes out of there is not an easy fraction.
 

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