Odpowiedzi

2010-03-23T09:30:50+01:00

H = 2r
w przekroju osiowym a = 2r = H
P = 1/2a*h = 72
1/2*H*H = 72
1/2*H² = 72 /*2
H² = 144
H = √√144 = 12
Pc = πr²+πrl
obliczam l
H = 12
r = 12/2 = 6 to l² = 6²+12²
l² = 36+144 = 180
l = √180 = 6√5
Pc = π*6²+π*6*6√5
Pc = 36π+36√5π = 36π(1+√5) cm²
V = 1/3πr²H
V = 1/3π*6²*12
V = 144π cm³