square root expression simplification




<snip>

I'd like to suggest an alternative, which I do so in the blissful
ignorance of the simplifier. I'd like to suggest that instead of
butting heads over which is the right way to do simplification, we
improve the configurability and/or modularity of the simplifier, 
so that the user can choose the right simplification policy.

What I have in mind includes:

1. assemble several 'standard' or useful configurations of the
simplifier and create a single function that lets the user
select configurations, or create new ones.

2. add health warnings in the documentation to clarify what is
meant by simplification.

I tend to think that simplification is more a question of implementing
a *policy* as opposed to getting a mathematically correct answer. 
What I mean is that most users, most of the time, want Maxima's
simplifier to do what they would do (e.g. sqrt(4) -> 2), and they
tend to get upset when this doesn't happen -- even when they know
better and know it is 'wrong'. So we should have a simplifier policy
('high_school_algebra') that implements this. But it would be
wrong to commit the Maxima simplifier to this policy in the large.

Leo


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