Arc Length Start with the formula for radian measure … … and multiply both sides by r to get … Arc length = radius times angle measure in radians.

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Presentation transcript:

Arc Length Start with the formula for radian measure … … and multiply both sides by r to get … Arc length = radius times angle measure in radians.

 Example 1: A circle has a radius of 7 in. Find the length of the arc subtended by a central angle of 4 rad. Arc length = radius times angle measure in radians.

 Example 2: A circle has a radius of 6cm. Find the length of the arc subtended by a central angle of 52°. Since the formula for arc length uses radian measure, we first change the degree measure to radians.

Arc length = radius times angle measure in radians.