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Arc and Sector

★★☆☆☆Middle School

📖Definition

An arc is a portion of the circle between two points. A sector is the region bounded by two radii and an arc.

l = (θ)/(360°) × 2π r

Arc length (θ in degrees)

l = rθ

Arc length (θ in radians)

A = (θ)/(360°) × π r²

Sector area (θ in degrees)

A = (1)/(2)r²θ

Sector area (θ in radians)

예제 1★★☆☆☆

Find the arc length and area of a sector with radius 10cm and central angle 72°.

Circular pipes, arc design

Pie charts

#geometry#circle#arc#sector