Category:Associates

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This category contains results about Associates in the context of Abstract Algebra.
Definitions specific to this category can be found in Definitions/Associates.

Let $\struct {D, +, \circ}$ be an integral domain.

Let $x, y \in D$.


Definition 1

$x$ is an associate of $y$ (in $D$) if and only if they are both divisors of each other.

That is, $x$ and $y$ are associates (in $D$) if and only if $x \divides y$ and $y \divides x$.


Definition 2

$x$ and $y$ are associates (in $D$) if and only if:

$\ideal x = \ideal y$

where $\ideal x$ and $\ideal y$ denote the ideals generated by $x$ and $y$ respectively.


Definition 3

$x$ and $y$ are associates (in $D$) if and only if there exists a unit $u$ of $\struct {D, +, \circ}$ such that:

$y = u \circ x$

and consequently:

$x = u^{-1} \circ y$


That is, if and only if $x$ and $y$ are unit multiples of each other.