mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...

, an element ''a'' of a

commutative ring In mathematics, a commutative ring is a ring in which the multiplication operation is commutative. The study of commutative rings is called commutative algebra. Complementarily, noncommutative algebra is the study of ring properties that are not sp ...

''A'' is called (relatively) prime to an ideal ''Q'' if whenever ''ab'' is an element of ''Q'' then ''b'' is also an element of ''Q''. A proper

ideal Ideal may refer to: Philosophy * Ideal (ethics), values that one actively pursues as goals * Platonic ideal, a philosophical idea of trueness of form, associated with Plato Mathematics * Ideal (ring theory), special subsets of a ring considere ...

''Q'' of a

''A'' is said to be primal if the elements that are not prime to it form an ideal.

References

*. Commutative algebra {{algebra-stub