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#48 strengthen inferences from assumptions

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nobody
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2008-02-17
2007-12-06
Anonymous
No

(%i1) assume(e>0,e<1);
(%o1) [e > 0, e < 1]

The following is OK:

(%i4) is(e^2<1);
(%o4) true

BUT the following is not OK:

(%i5) is(e^2<2);
(%o5) unknown

If it knows that e^2 is less than 1 then it should also know that e^2 is less than 2 (or any other number larger than 1) but it does not.

Discussion

  • Stavros Macrakis

    • labels: 887072 -->
     
  • Stavros Macrakis

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    Though it's true that it would be nice if Maxima could determine that e^2<2, this is not an "incorrect result"; "unknown" means that Maxima cannot tell whether the relation is true.

    So I have reclassified this as a feature request -- that is, a request that Maxima do a better job.

     
  • Robert Dodier

    Robert Dodier - 2008-02-17
    • summary: is() function gives incorrect results --> strengthen inferences from assumptions
     
  • Robert Dodier

    Robert Dodier - 2008-02-17

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    Attempted to make title more descriptive.

     

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