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From: John H Meyers on 10 Mar 2010 19:53
On 3/10/2010 11:55 AM, Merciadri Luca wrote:

> I thought I had already specified the '=0' part.

You don't actually need to,
because the generalized meaning of "solving an expression"
is actually defined as "make the entire expression value zero"

If the expression happens to be "leftside=rightside"
the "=" operator actually translates into a subtraction
when evaluating, to produce a single value anyway,
from any valid algebraic expression,
whether containing "=" or not,
and finally making that single numeric value zero.

As an example, '4=3' \->NUM results in 1,
because "=" is treated as the lowest priority
of all algebraic operators, ultimately meaning "-"

By the same token, either algebraically or numerically solving
'4-2*X=3-X' for X results in an entire expression value of 1
when X is zero, or an entire expression value of zero when X is 1,
achieving the goal and solution for X at the latter point,
in exactly the same steps as "solving" the expression '(4-2*X)-(3-X)'
for where its entire single value is zero.

Appending "=0" to any expression not yet containing "="
is therefore not necessary for "solving,"
and in fact only wastes a little time :)

[r->] [OFF]
From: Veli-Pekka.Nousiainen on 12 Mar 2010 03:15
Merciadri Luca wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hi,
>
> I was solving chemistry problems with my 50g, when I realized that
> SOLVEX fails with an equation of the 2nd degree where products are not
> indicated using dots.
>
> For example, using RPN:
>
> 2:'x^2 + x(x-4) +3x'
> 1:SOLVEX
__________________________________________
CASCFG
'X^2+X*(X-4)+3*X'
SOLVEVX
=>
{ 'X=0' 'X=1/2' }
@ VPN
___________________________________________
> won't work, and will display an error message to explain that the
> expression cannot be reduced to a canonical form. Is it normal?
> I would accept this as a normal thing iff the 50g was using
> parentheses to compute, say,<f, g>, where f and g are two functions,
> but I do not think that it has this kind of capabilities.
>
> Thanks.
> - --
> Merciadri Luca
> See http://www.student.montefiore.ulg.ac.be/~merciadri/
> - --
>
> Life is like a box of chocolate, you never know what you're gonna
> get.
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> Comment: Processed by Mailcrypt 3.5.8<http://mailcrypt.sourceforge.net/>
>
> iEYEARECAAYFAkuXmrcACgkQM0LLzLt8MhwslACfdR3FOYu79O8kKufJ2uvGl7l2
> mYcAn3/mkCtO+bKZmScl4Gh6o0IT/8eW
> =ybFK
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From: Virgil on 12 Mar 2010 03:54
Merciadri Luca wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Hi,
>
> I was solving chemistry problems with my 50g, when I realized that
> SOLVEX fails with an equation of the 2nd degree where products are not
> indicated using dots.
>
> For example, using RPN:
>
> 2:'x^2 + x(x-4) +3x'
> 1:SOLVEX

> won't work, and will display an error message to explain that the
> expression cannot be reduced to a canonical form. Is it normal?
> I would accept this as a normal thing iff the 50g was using
> parentheses to compute, say,<f, g>, where f and g are two functions,
> but I do not think that it has this kind of capabilities.

Try
'x^2 + x*(x-4) +3*x'
'x'
SOLVE
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