11.4 Circumference and Arc Length

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Presentation transcript:

11.4 Circumference and Arc Length Arc of a Circle

Definitions Circumference-The enclosing boundary of a curved geometric figure, esp. a circle. Arc length- A fraction of the circumference

Theorem The equation of the circumference

Find the Circumference Radius 7

Find the Circumference Radius 7

Find the Arc Length (often called S) Find the Central angle θ (the angle whose vertex is at the center), Then multiply the Circumference by the fraction Central angle 360°

Find the Arc Length Given a Central angle of 60° and a Radius of 12.

Find the Arc Length Given a Central angle of 60° and a Radius of 12.

Find the Central angle Let R = 8 inches Length of S = 16.76 inches Use 3.14 for pi

Find the Central angle Let R = 8 inches Length of S = 16.76 inches. Use 3.14 for pi

Find the Central angle Let R = 8 inches Length of S = 16.76 inches. Use 3.14 for pi

Find the Circumference Central Angle 45° Arc Length 10.2

Find the Circumference Central Angle 45° Arc Length 10.2

Homework Page 686 – 687 # 15 – 38, 40 45, 47