Understanding Area of a Sector Using Radians

This lesson covers finding the area of a sector with a central angle of 120° using radians. It begins with an introduction to the concept and the formula for area in radians. The lesson then explains how to convert degrees to radians by multiplying by π/180. Finally, it demonstrates the calculation of the area using the formula, resulting in approximately 67.26 square cm.

What is the central angle of the yellow sector in degrees?

• 60°

• 180°

• 90°

• 120°

What is the formula for the area of a sector in terms of radians?

• 1/2 * r^2 * theta

• r^2 * theta

• 1/3 * r^2 * theta

• r * theta

How do you convert degrees to radians?

• Divide by 180

• Multiply by π/180

• Multiply by 180/π

• Add π

What is the converted angle of 120° in radians?

• 2π/3

• π/2

• π

• π/3

What is the approximate area of the sector in square centimeters?

• 60 cm²

• 67.26 cm²

• 64 cm²

• 70 cm²