Question

determinar a área do setor circular de raio 8 cm ângulo central 120°

Answer 1

$A = \dfrac{ \alpha}{180}.\dfrac{\pi.r^2}{2} \\ \\ \\ A = \dfrac{ 120}{180}.\dfrac{\pi.8^2}{2} \\ \\ \\ A = \dfrac{2}{3}.\dfrac{\pi.64}{2} \\ \\ \\ A = \dfrac{2}{3}.32 \pi \\ \\ \\ A = \dfrac{2.32 }{3} . \pi\\ \\ \\ =\ \textgreater \ A = \dfrac{64}{3}. \pi ~cm^2$