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Mathematica issue

  1. Jun 5, 2008 #1
    [SOLVED] mathematica issue

    This is from Mathematica 6.0. Is this a bug in Mathematica? Supposedly the second output is precise to 100 digits!

    Last edited: Jun 5, 2008
  2. jcsd
  3. Jun 5, 2008 #2


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    Science Advisor

    I think you are running into a machine precision issue with the way your equation is entered. Take a look in the help files in 3.1.6.

  4. Jun 5, 2008 #3
    Hmmm...I thought the N[ ] function caused the expression to be evaluated in arbitrary precision mode. How can I get that expression in arbitrary precision mode?
  5. Jun 6, 2008 #4


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    Homework Helper

    Hi ehrenfest,

    I believe the problem occurs when you give the value to x; at that point machine precision is used for x which carries over to the rest of the calculation. If you want 100 digits in arbitrary precision, you could use:


    and then calculate

    N[(1 + x)^(1/3) - 1 - x/3 + (x^2)/9 - 5 (x^3)/81, 100]
  6. Jun 6, 2008 #5
    problem solved!
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