wrong Factor[] result
- To: mathgroup at smc.vnet.net
- Subject: [mg25649] wrong Factor[] result
- From: Gianluca Gorni <gorni at dimi.uniud.it>
- Date: Wed, 18 Oct 2000 02:52:23 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hello!
Take the polynomial
pol = a^2 + 2b^2;
and factorize it this way:
res = Factor[pol, Extension -> {Sqrt[-2]/3}]
Out -> ((-3*I*a + Sqrt[2]*b)*(3*I*a + Sqrt[2]*b))/9
This result is wrong! Just expand it:
Expand[res]
Out -> a^2 + (2b^2)/9
I get a correct result if I factor for example as
Factor[pol, Extension -> {Sqrt[-2]}]
My version is 4.0 for PowerMac.
Gianluca Gorni
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