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4.9.1 Introduction to Polynomials
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An object of type POLY in CoCoA represents a polynomial. To fix
terminology: a polynomial is a sum of terms; each term is the product
of a coefficient and power-product, a power-product being a product of
powers of indeterminates. (In English it is standard to use
monomial
to mean a power-product, however, in other languages, such as Italian,
monomial connotes a power product multiplied by a scalar. In the
interest of world peace, we will use the term power-product in those
cases where confusion may arise.)
The following are CoCoA polynomials:
Use R ::= QQ[x,y,z];
F := 3xyz + xy^2;
F;
xy^2 + 3xyz
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Use R ::= QQ[x[1..5]];
Sum([x[N]^2 | N In 1..5]);
x[1]^2 + x[2]^2 + x[3]^2 + x[4]^2 + x[5]^2
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CoCoA always keeps polynomials ordered with respect to the
term-orderings of their corresponding rings.
The following algebraic operations on polynomials are supported:
F^N, +F, -F, F*G, F/G if G divides F, F+G, F-G,
where F, G are polynomials and N is an integer. The result may be a
rational function.
Use R ::= QQ[x,y,z];
F := x^2+xy;
G := x;
F/G;
x + y
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F/(x+z);
(x^2 + xy)/(x + z)
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F^2;
x^4 + 2x^3y + x^2y^2
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F^(-1);
1/(x^2 + xy)
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