Re: int(1/x^2,x,-1,1)
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Re: int(1/x^2,x,-1,1)
Is Derive XM shareware? Do you where we could download it if it is? Thanks
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From: Geoff H <galois@cyberg8t.com>
To: CALC-TI@LISTS.PPP.TI.COM
Date: Friday, June 20, 1997 3:39 PM
Subject: int(1/x^2,x,-1,1)
>A few more thoughts on this thread:
>_____________________
>Synopsis:
>
>The '85 responds to fnInt(1/x^2,x,-1,1) (after a yawning gap of time)
>with "ERROR 02 DIV BY ZERO."
>
>Derive XM for DOS gives INT(1/x^2,x,-1,1) = -2
>
>and from Michael Keyton's report, the TI-92 has
>INT(1/x^2,x,-1,1) = infinity.
>
>It seems the '92's answer is the best guess of all!
>_______________________________________________________
>So here's another test:
>The '85 responses to both fnInt(1/x,x,0,1) and fnInt(1/x,x,-1,1) are
>"ERROR 33 TOL NOT MET" (unless tol is cranked to about 1.9) and
>"ERROR 02 DIV BY ZERO," respectively.
>
>Derive XM responds to INT(1/x,x,0,1) with infinity,
>while INT(1/x,x,-1,1) gives -i*pi, which looks like an
>application of Cauchy's residue theorem?!
>
>What does the '92 do?
>________________________________________________________
>
>Geoff Hagopian,
>Palm Desert, CA
>
>
>
>Digest:
>.... I don't have the '92, but I'm a Deriver from way back. One of
>.... the curious bugs in Derive is that, if you integrate 1/x^2 from
>.... -1 to 1, it give you -2.
>... <The '92> gives infinity.
>... What version of Derive are you using?
>.. I have Derive XM 3.05
>. David Stoutmeyer really works hard to purge incorrect solutions
>. in Derive. <snip...>
>
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