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Measure

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In mathematics, measure can mean the amount of degrees in an angle, the length of a line segment, or a function that assigns a number to subsets of a given set.

Contents

Line Segments

The measure of \overline{AB} is indicated by AB, without the bar on top. If \overline{AB}\cong\overline{CD}, then AB=CD.

Angles

The measure of \angle ABC is indicated by \mbox{m}\angle ABC. If \angle ABC\cong\angle DEF, then \mbox{m}\angle ABC=\mbox{m}\angle DEF.

The measure of an angle can expressed in degrees or in radians.

Circular arcs

The measure of an arc of a given circle is given by the measure of the central angle subtended by it.

Sets

The measure of a set is known as the set's cardinality. If S=\{-2,\,\pi,\,7\}, then the cardinality of set S is 3.

See Also

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