Details

This message is generated when both the Modulus and Extension options are set to nondefault values.
This message can be generated by Factor, FactorList, FactorSquareFree, FactorSquareFreeList, PolynomialGCD, and Together.
Off[message] switches off the message; On[message] switches it on. For example: Off[General::mext].

Examples

The Modulus and Extension options cannot in general be used at the same time:

Wolfram Language code: Factor[x ^ 2 - 2, Modulus -> 2, Extension -> Sqrt[2]]

Both options can be used separately:

Wolfram Language code: Factor[x ^ 2 - 2, Modulus -> 2]

Wolfram Language code: Factor[x ^ 2 - 2, Extension -> Sqrt[2]]

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