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<record version="8" id="5986">
 <title>arg min and arg max</title>
 <name>ArgMin</name>
 <created>2004-07-07 22:39:15</created>
 <modified>2007-07-02 22:42:43</modified>
 <type>Definition</type>
 <creator id="5987" name="kshum"/>
 <author id="5987" name="kshum"/>
 <classification>
	<category scheme="msc" code="00A05"/>
 </classification>
 <defines>
	<concept>argmin argmax</concept>
 </defines>
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 <content>For a real-valued function $f$ with domain $S$, $\arg \min_{x \in S} f(x)$ is the set of elements in $S$ that achieve the global minimum in $S$,
\[
 {\arg \min}_{x \in S} f(x) = \{ x \in S :\, f(x) = \min_{y\in S} f(y) \}.
\]

$\arg \max_{x \in S} f(x)$ is the set of elements in $S$ that achieve the global maximum in $S$,
\[
 {\arg \max}_{x \in S} f(x) = \{ x \in S :\, f(x) = \max_{y\in S} f(y) \}.
\]


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