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Variable in Exponents

  • Thread starter Mentallic
  • Start date
  • #1
Mentallic
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Homework Statement


Solve for x
[tex]5^{3x}-12^x+2^{\frac{x}{2}}=5[/tex]


Homework Equations


logarithm rules?
log(a+b)=?


The Attempt at a Solution


Taking the logarithm of both sides only makes things worse from what I can see.
So really, I don't know how to start.
[tex]x\approx 0.386744[/tex]
 

Answers and Replies

  • #2
tiny-tim
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Solve for x
[tex]5^{3x}-12^x+2^{\frac{x}{2}}=5[/tex]
hmm … that's 125x - 12x + (√2)x = 5 …

i can't see any way of solving that except by numerical approximation :redface:
 
  • #3
Mentallic
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Is this possibly due to the lack of understanding with this maths or because it cannot be solved with an exact answer? Such as 'exact' answers with a series of logarithms, even though the logs themselves are approximated.
Any idea how I could go about obtaining a reasonably accurate numerical approximation?
 

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