Simple log question

  • #1
Help me solve for x in detail please:

8^x+13^x=108

Simply done graphically, but algebraically?
 

Answers and Replies

  • #2
Zurtex
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It can't be solved with logs or anything like that.
 
  • #3
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?
 
  • #4
Zurtex
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You can only approximate the solution, which is:

[tex]x \approx 1.682790571570192534987737142973064792462[/tex]
 
  • #5
dextercioby
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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.
 
  • #6
you can solve it by using newton-raphson method
 
  • #7
Curious3141
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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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