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The issue seems to be fixed as of Version 10.1.


Just came across the strangest bug under both Mathematica 9.0.0 and 9.0.1. If one enters:

Solve[m == p Sin[x] && -Pi/2 < x < Pi/2, x]

... then Mathematica whirrs and whirrs (running on my Mac Pro with OS X 10.6.8), and doesn't seem to produce any answer (I gave up after a few minutes). But if one changes symbol p to something that 'sorts' earlier than an m, such as an 'a' or 'b', then it works correctly:

Solve[m == b Sin[x] && -Pi/2 < x < Pi/2, x]

Solve::nsmet: This system cannot be solved with the methods available to Solve.

Obviously, one can add assumptions on p or b to make it solve, but that is not the issue being raised.

Is this just a Mac issue, or are others experiencing the same on other platforms?

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    $\begingroup$ Ah, I've seen this one before... I remember an answer/comment from Daniel saying that this was a hashing problem and cannot be fully fixed, but they address specific and common cases as they encounter them. $\endgroup$ – rm -rf Feb 8 '13 at 19:04
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    $\begingroup$ Here's the post I was thinking of: stackoverflow.com/q/5402214 $\endgroup$ – rm -rf Feb 8 '13 at 19:06
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    $\begingroup$ Different issue. The hashing one only causes a slowdown in dealing with large, deep expressions. Will investigate. $\endgroup$ – Daniel Lichtblau Feb 8 '13 at 19:54
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    $\begingroup$ Reported as a bug. $\endgroup$ – Daniel Lichtblau Feb 8 '13 at 20:03
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    $\begingroup$ FWIW: same behavior in Windows version (Mathematica 9.0.0.0 under Windows 7) $\endgroup$ – stevenvh Feb 9 '13 at 10:58
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This has been confirmed and reported as a bug (see comments).

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