Solve 8^x+13^x=108: Step-by-Step Algebraic Guide

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Discussion Overview

The discussion centers around the equation 8^x + 13^x = 108, specifically focusing on methods for solving it algebraically. Participants explore the feasibility of finding an exact solution versus approximating the solution.

Discussion Character

  • Debate/contested, Mathematical reasoning

Main Points Raised

  • One participant requests a detailed algebraic solution for the equation.
  • Another participant asserts that the equation cannot be solved using logarithms or similar methods.
  • A participant expresses uncertainty about the solvability of the equation, indicating they may have overlooked a method.
  • One participant provides an approximate solution for x, suggesting that it is around 1.682790571570192534987737142973064792462.
  • Another participant agrees that an exact algebraic solution is not possible and notes that most transcendental equations cannot be solved exactly.
  • One participant suggests that the Newton-Raphson method can be used to approximate the solution.
  • A later reply reiterates the use of the Newton-Raphson method, emphasizing that it yields only an approximate solution and confirms the absence of an exact solution method.

Areas of Agreement / Disagreement

Participants generally agree that the equation cannot be solved exactly and that approximation methods, such as the Newton-Raphson method, are necessary. However, there is some uncertainty regarding the methods available for approaching the problem.

Contextual Notes

Participants note that the equation is transcendental, which typically limits the possibility of finding exact solutions. The discussion reflects a reliance on numerical methods for approximation.

beethoven'smahomeboy
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Help me solve for x in detail please:

8^x+13^x=108

Simply done graphically, but algebraically?
 
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It can't be solved with logs or anything like that.
 
I figured as much after working with it for a while, but I thought I might have just been missing something. How does one solve it then?
 
You can only approximate the solution, which is:

[tex]x \approx 1.682790571570192534987737142973064792462[/tex]
 
I think you can't do it,without a calculator.Maple returns [itex]\left\{ x=1.\,68279\,0572\right\}[/itex],but it can't be solved algebraically.In fact,most transcendental equations can't be solved.

Daniel.
 
you can solve it by using Newton-raphson method
 
quentinchin said:
you can solve it by using Newton-raphson method

Only approximate, not an exact solution. There is no exact solution method.
 

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