I've set the CAS to complex mode, but the symbolic commands don't produce
complex solutions, e.g.
'4*x^3+8*x-4' SOLVEVX
gives an empty list.
Am I doing something wrong? Does the CAS understand complex numbers?
|
|
0
|
|
|
|
Reply
|
Borris
|
12/18/2005 4:40:23 PM |
|
In article
<1134924023.58fec87c58f249b740f40b921c33786d@roc.usenetexchange.com>,
Borris <none@none.com> wrote:
> I've set the CAS to complex mode, but the symbolic commands don't produce
> complex solutions, e.g.
> '4*x^3+8*x-4' SOLVEVX
> gives an empty list.
>
> Am I doing something wrong? Does the CAS understand complex numbers?
As you have entered it, your variable seems to be the lower case'x',
not the upper case 'X'.
The calculator is case sensitive, and the default variable for SOLVEVX
is an upper case 'X', not a lower case 'x'.
|
|
0
|
|
|
|
Reply
|
Virgil
|
12/18/2005 7:23:05 PM
|
|
Virgil wrote:
> In article
> <1134924023.58fec87c58f249b740f40b921c33786d@roc.usenetexchange.com>,
> Borris <none@none.com> wrote:
>
>
>>I've set the CAS to complex mode, but the symbolic commands don't produce
>>complex solutions, e.g.
>>'4*x^3+8*x-4' SOLVEVX
>>gives an empty list.
>>
>>Am I doing something wrong? Does the CAS understand complex numbers?
>
>
> As you have entered it, your variable seems to be the lower case'x',
> not the upper case 'X'.
>
> The calculator is case sensitive, and the default variable for SOLVEVX
> is an upper case 'X', not a lower case 'x'.
Sorry, I used an upper X
|
|
0
|
|
|
|
Reply
|
Borris
|
12/18/2005 10:27:36 PM
|
|
Strange. When I do '4*X^3+8*X-4' SOLVEVX (in complex mode, FIX 2) I
get:
{ X=(-0.23,-1.47) X=(-0.23,1.47) X=0.45 }
You might have a strange flag setting; do CASCFG and try again.
-Joe-
|
|
0
|
|
|
|
Reply
|
Joe
|
12/18/2005 11:25:09 PM
|
|
In article
<1134944856.efa44d290a5d4ace54b050d099bedb85@roc.usenetexchange.com>,
Borris <none@none.com> wrote:
> Virgil wrote:
> > In article
> > <1134924023.58fec87c58f249b740f40b921c33786d@roc.usenetexchange.com>,
> > Borris <none@none.com> wrote:
> >
> >
> >>I've set the CAS to complex mode, but the symbolic commands don't produce
> >>complex solutions, e.g.
> >>'4*x^3+8*x-4' SOLVEVX
> >>gives an empty list.
> >>
> >>Am I doing something wrong? Does the CAS understand complex numbers?
> >
> >
> > As you have entered it, your variable seems to be the lower case'x',
> > not the upper case 'X'.
> >
> > The calculator is case sensitive, and the default variable for SOLVEVX
> > is an upper case 'X', not a lower case 'x'.
>
> Sorry, I used an upper X
The HP calculators will not find exact irrational zeros to a cubic
polynomial, but can find approximate ones.
An alternate form for getting approximate zeros is to enter [ 4 0 8 -4]
as the vector of coefficients and then use the PROOT command to get a
vector of the zeros. This works regardless of flag settings.
|
|
0
|
|
|
|
Reply
|
Virgil
|
12/19/2005 12:54:00 AM
|
|
Set your calculator to approximate mode ,then using SOLVEVX will give
the numerical answer!
|
|
0
|
|
|
|
Reply
|
dongdong
|
12/19/2005 9:11:45 AM
|
|
|
5 Replies
379 Views
(page loaded in 0.087 seconds)
|