PolynomialReduce

PolynomialReduce[poly, {poly1, poly2, ...}, {x1, x2, ...}] yields a list representing a reduction of poly in terms of the polyi. The list has the form {{a1, a2, ...}, b}, where b is minimal and a1*poly1 + a2*poly2 + ... + b is exactly poly.

Examples

Reduce a polynomial:

PolynomialReduce[x^2 + y^2, {x + y, x - y}, {x, y}]
(* {{x/2 - y/2, x/2 + y/2}, 0} *)

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