Hitunglah luas permukaan bangun ruang berikut. (Nomor a).
DB45
R tab = r kerucut = 1/2 (10)= 5 t tabung =t₁ = 18 tk = 12 s = √(tk²+r²) =√(12²+5²)= 13
luas permukaan bangun = luas alas tab + luas selimut tab + luas selimut kerucut L = π r² + 2π r t₁ + π r s L = π r (r + 2 t₁ + s) L = (3,14)(5)(5+36+13) L = (15,7)(54) = 847,8 cm²
t tabung =t₁ = 18
tk = 12
s = √(tk²+r²) =√(12²+5²)= 13
luas permukaan bangun = luas alas tab + luas selimut tab + luas selimut kerucut
L = π r² + 2π r t₁ + π r s
L = π r (r + 2 t₁ + s)
L = (3,14)(5)(5+36+13)
L = (15,7)(54) = 847,8 cm²