Question

AB is a chord of a circle with centre O and radius 4 cm. AB is of length 4 cm. Find the areas of the sector of the circle formed by chord AB.

Answer 1

Length of the chord = 4 cm 

Radius of circle = 4 cm 

(This chord and radius makes an equilateral triangle) 

So, 

Q = 60° (in equilateral triangle) 

Area of sector = \(\frac{θ}{360°}\timesπr^2\)

= \(\frac{60°}{360°}\timesπ\times4\times4\)

= \(\frac{1}{6}\timesπ\times16\) 

= \(\frac{8π}3\) cm²