Berapa panjang busur lingkaran dengan sudut pusat 60° dan diameter 40cm

jawab
a= 60
d = 40 cm

k = pi d = 3,14 x 40 = 125,6 cm
panjang busr = 60/360 K = 1/6 (125,6) cm =20,93

[tex] r = \frac{1}{2}d = 20 \\ b = \frac{ \alpha }{360} \times 2\pi r \\ \: \: \: = \frac{60}{360} \times 2(3.14)(20) \\ \: \: \: = 20.93 \: cm[/tex]