Question

Suatu kerucut mempunyai alas dgn diameter 12 cm dn tinggi 8 cm. jmlh luas permukaan kerucut adalah........cm

Answer 1

S = akar (6² + 8²)
s = akar (100)
s = 10 cm

Lp = (3,14 x 6²) + (1/3 x 3,14 x10²)
     = 113,04 cm² + 104,7 cm²
     = 217,74 cm²

Answer 2

D alas =12 r=6
t = 8
s = phytagoras 6,8,... = 10
lp=?
lp= π r (r+s)
 =3.14 × 6 (6+10 )
 = 18.84  × (16)
 = 301.4 cm²