Primitive part and content: Difference between revisions

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==Over the integers==
For a polynomial with integer coefficients, the content may be either the [[greatest common divisor]] of the coefficients of its [[additive inverse]]. The choice is somehow arbitrary, and may depend on a further convention, which is commonly that the [[leading coefficient]] of the primitive part be positive.
 
For example, the content of <math>-12x^3+30x-20</math> may be either 2 or –2, since 2 is the greatest common divisor of –12, 30, and -20. If one chooses 2 as the content, the primitive part of this polynomial is
:<math>-6x^3+15x-10 = \frac{-12x^3+30x-20}{2},</math>
and thus the primitive part–contentprimitive–part–content factorization is
:<math>-12x^3+30x-20 = 2 (-6x^3+15x-10).</math>
For aesthetically reasons, one often prefer choosing a negative content, here –2, for having the primitive part–contentprimitive–part–content factorization
:<math>-12x^3+30x-20 =-2 (6x^3-15x+10).</math>