Sudut AOB = 60°,OA = OB = 20cm. a. Hitunglah panjang busur AB b. Hitunglah luas juring OAB

a. Panjang Busur AB
[tex] = \frac{ {60}^{o} }{ {360}^{o} } \times 2 \times 3.14 \times 20 \\ = 20.93cm[/tex]
b. Luas Juring OAB
[tex] = \frac{ {60}^{o} }{ {360}^{o} } \times 3.14 \times 20 \times 20 \\ = 209.3 \: {cm}^{2} [/tex]