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Is [itex]x = - lo{g_2}(x)[/itex] a complex number

  1. Jun 5, 2012 #1
    If I have a function such that [itex]x = - lo{g_2}(x)[/itex], then must x be a complex number? Thanks.
     
  2. jcsd
  3. Jun 5, 2012 #2

    D H

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    There are complex solutions to this, but there is one solution that is real.
     
  4. Jun 5, 2012 #3

    haruspex

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    At x = 1, LHS is the larger; at x = 1/2, RHS is the larger. Since both functions are continuous in that range, there must be a real solution between the two.
     
  5. Jun 5, 2012 #4

    D H

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    That's the number I was thinking of.
     
  6. Jun 6, 2012 #5
    also, it is an equation, not a function
     
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