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 <title>algebraically dependent</title>
 <name>AlgebraicallyDependent</name>
 <created>2003-09-25 17:57:50</created>
 <modified>2006-02-24 19:57:30</modified>
 <type>Definition</type>
 <creator id="2727" name="mathcam"/>
 <author id="2727" name="mathcam"/>
 <classification>
	<category scheme="msc" code="12F05"/>
	<category scheme="msc" code="11J85"/>
 </classification>
 <defines>
	<concept>algebraically independent</concept>
	<concept>algebraic dependence</concept>
	<concept>algebraic independence</concept>
 </defines>
 <related>
	<object name="DependenceRelation"/>
 </related>
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 <content>Let $L$ be a field extension of a field $K$.  Two elements $\alpha, \beta$ of $L$ are \emph{algebraically dependent} if there exists a non-zero polynomial $f(x,y)\in K[x,y]$ such that $f(\alpha,\beta)=0$.  If no such polynomial exists, $\alpha$ and $\beta$ are said to be \emph{algebraically independent}.

More generally, elements $\alpha_1,\ldots,\alpha_n\in L$ are said to be algebraically dependent if there exists a non-zero polynomial $f(x_1,\ldots,x_n)\in K[x_1,\ldots,x_n]$ such that $f(\alpha_1,\alpha_2,\ldots,\alpha_n)=0$.  If no such polynomial exists, the collection of $\alpha$'s are said to be algebraically independent.</content>
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