JAMB - Mathematics (2016 - No. 18)
Calculate the perimeter of a sector of a circle of raduis 12cm and angle 60o.
(12 + 4\(\pi\))cm
(24 + 4\(\pi\))cm
(12 + 6\(\pi\))cm
(24 + 6\(\pi\))cm
Giải thích
Perimeter = 2r + \(\frac{\theta}{360}\) x 2\(\pi\)r
= 2(12) + \(\frac{60}{360}\) x 2 x \(\pi\) x 12
= (24 + 4\(\pi\))cm
= 2(12) + \(\frac{60}{360}\) x 2 x \(\pi\) x 12
= (24 + 4\(\pi\))cm