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Stupid Equation

  1. Dec 24, 2004 #1
    How do I solve the following equation?

    8n^2 = 64 n lg(n); (0 < n)

    n = 8lg(n)
    10^n = 10^8 n
    ...??? How do I isolate n?
  2. jcsd
  3. Dec 24, 2004 #2


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    Who says u can???It's typically a transcendental equation.I suggest either graphical method (intersaction of graphs) (done by computer,maybe),or taking a calculator and "solving it through tries".Your equation may have 0,1 or maximum 2 solutions.

  4. Dec 24, 2004 #3
    I already did that with mathematica and got that one solution is x ~ 6.5... I just wanted to know if there was any algebraic solution...

    I study running times of some algorithms and got this questions: for that values of n is the following inequality true:
    8n^2 < 64 n lg(n)

    Is there no analytical approach. This is a potential exam question and were not allowed to use calculators...
  5. Dec 24, 2004 #4

    matt grime

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    Is n supposed to be an integer?
  6. Dec 24, 2004 #5
    Yes, n is integer (input size for algorithm) but I'm interested in both cases. (real/integer)
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