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Complex function ?

  1. Nov 1, 2011 #1
    hi,
    I'd like to ask whether the function f:y=|ln(x)| (|| denotes the absolute value) is complex. I'm a little bit confused because it is defined also for negative numbers in reals. Is the "negative part" classified as a complex function even if it has no imaginary part ?

    thanx
     
  2. jcsd
  3. Nov 1, 2011 #2

    mathman

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    Real numbers may be positive or negative. Real numbers are a subset of complex numbers where the imaginary part is 0, whether the real part is positive or negative.
     
  4. Nov 1, 2011 #3
    Thanks, my question is , can I include that part of the plot where the independent variable is negative in real analysis ?
     
  5. Nov 2, 2011 #4

    mathman

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    If x is < 0, ln(x) is imaginary, but |ln(x)| is non-negative real. There is no rule that says you can't plot it.
     
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