#1223 integration integrate(1/((x-3)^4+1/2),x,0,1);=0????

closed
nobody
None
5
2007-06-28
2007-06-13
Anonymous
No

In the Moses tutorial, there is the integration
%i1) integrate(1/((x-3)^4+1/2),x,0,1);
(%o1) 0

while the true result is 0.02880......
which was obtained using romberg

(%i2) romberg(1/((x-3)^4+1/2),x,0,1);

Is that a bug, or is there a trick.

(%o2) 0.028806333924554

Discussion

  • Harald Geyer

    Harald Geyer - 2007-06-13

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    I don't know, what the submitter (alas he left no contact info)
    did wrong, but I can't reproduce this bug with 5.11.0 and 5.12.0
    (both clisp).

    Maxima gives a very long expression, which is evaluated by
    float() to something almost equal to the result of romberg().

     
  • Raymond Toy

    Raymond Toy - 2007-06-13

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    Recent CVS version doesn't return 0. It returns some really long and hairy expression that can't be printed because it's too wide. But

    radcan(sqrtdenest(integrate(1/((x-3)^4+1/2),x,0,1)));

    returns something sensible, which evaluates to 0.028806...

    What version of maxima?

    Marking this as pending.

     
  • Raymond Toy

    Raymond Toy - 2007-06-13
    • status: open --> pending
    • summary: integration integrate(1/((x-3)^4+1/2),x,0,1);=0????
      --> integration integrate(1/((x-3)^4+1/2),x,0,1);=0????
     
  • SourceForge Robot

    • status: pending --> closed
     
  • SourceForge Robot

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    This Tracker item was closed automatically by the system. It was
    previously set to a Pending status, and the original submitter
    did not respond within 14 days (the time period specified by
    the administrator of this Tracker).

     

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