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+--- Thread: Finding roots of polynomial (/thread-18083.html)
Finding roots of polynomial - WedgeAntilles - 02-26-2022 03:47 PM
Hi there,
I am reading the hp prime user guide.
On page 55, there is an example to find the roots of 2x^2+3x-2.
I do as the manual says, proot(2*x^2+3*x-2) and the hp prime answers []
Inside the braclets there is no info about the 2 roots.
Note: the ^inside the proot(2*x^2+3*x-2) , I dont input it in the hp prime.
What am I doing wrong??
Many thanks,
RE: Finding roots of polynomial - Tim Roche - 02-26-2022 11:01 PM
proot() is expecting an array of coefficients for the input polynomial. So, for your polynomial
proot( [2 3 -2] )
and hp prime's answer
[-2.,0.5]
RE: Finding roots of polynomial - john gustaf stebbins - 02-26-2022 11:22 PM
The example with the polynomial worked for me. Until I assigned a value to x. Now I get an empty matrix for an answer.
Trying to remember how to unassign a variable in CAS. :^(
RE: Finding roots of polynomial - john gustaf stebbins - 02-27-2022 12:18 AM
purge(x)
RE: Finding roots of polynomial - WedgeAntilles - 02-27-2022 08:53 AM
Hi there,
After doing purge(x), it worked fine.
I was begining to think the calc had a bug....
Many thanks!