On Wed, 9 Jun 2010, Richard Fateman wrote:
<
< > [1,-1] (i.e. essentially the output of solve(x^2-1,x) ).
< >
< >
< >
< Not adequate, really. is sqrt(1) + sqrt(1) then [2,0,-2]?
You've not provided enough information, so I would say the answer
is
[[2,0],[0,-2]].
My narrow point is that sqrt is a multi-valued function. Repeated invocations
must either know that they are related, i.e. you are referring to the
same element in the same branch (to the same 'sqrt(1)'), or pursue
the complete collection of branches.
My larger point is that CAS deal with multi-valued functions
incorrectly. This causes a lot of the 'bugs' which are filed and
discussed on this list.
I am no longer familiar enough with Maple to know if its RootOf
has any capabilities beyond place-holding.
Leo
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