a) l =15
sin beta = 0,6
h/l =sin beta
h =l*sin beta =15 * 0,6 =9
h = 9 cm
r^2 =l^2 -h^2 = 225 -81 = 144
r = 12
r =12cm
V =pi*r^2*h = pi*(12^2)*9 =pi *144*9 = pi*1296
V =1296*pi cm^3 = (w przybliżeniu ) 4069,44 cm^3
z.2
tg beta =2,4 oraz l = 13 cm
tg beta =h/r --> h = r *tg beta
h^2 =l^2 - r^2
r^2*(tg beta)^2 + r^2 = l^2
r^2 *[( tg beta)^2 + 1 ] = l^2
r^2 = [13^2 ] :[(2,4)^2 +1] = 169/6,76 = 25
czyli r = 5
r = 5cm
h^2 = l^2 - r^2 = 169 - 25 = 144
czyli h =12
h =12 cm
V =pi*r^2*h = pi * 25*12 = pi*300
V =300*pi cm^3
W przybliżeniu
V = 942 cm^3
