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wrong Factor[] result


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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 +---------------------------------+
 | Gianluca Gorni                  |
 | Universita` di Udine            |
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