Question

Bila panjang garis pelukis kerucut 13cm,dan keliling alasnya 31,4cm,maka volume kerucut adalah.............

Answer 1

Volume = phi x r x r x t
Cari r =
K = 2 x phi x r
R = K / 2 phi = 31,4 / 2 x 3,14 = 5 cm
Cari t =
T2 = s2 - r2 = 13^2 - 5^2 = 169 - 25 = 144
T = 12
V = 3,14 x 5 x 5 x 12 = 942 cm2