JAMB - Mathematics (1979 - No. 33)
An arc of circle of radius 2cm subtends an angle of 60º at the centre. Find the area of the sector
\(\frac{2 \pi}{3}\)cm2
\(\frac{\pi}{2}\)cm2
\(\frac{\pi}{3}\)cm2
\(\pi\)cm2
คำอธิบาย
Area of a sector \(\frac{\theta}{360}\) x \(\pi\)r\(^2\)
= \(\frac{60^o}{360^o}\) x \(\pi\)2\(^2\)
= \(\frac{2 \pi}{3}\)cm2
= \(\frac{60^o}{360^o}\) x \(\pi\)2\(^2\)
= \(\frac{2 \pi}{3}\)cm2