Odpowiedź:
zad 1
a - krawędź sześcianu = 8 cm
Pc - pole całkowite = 6a² = 6 * 8² cm² = 6 * 64 cm² = 384 cm²
V - objętość = a³ = 8³ cm³ = 512 cm³
b)
a = 1,2 cm
Pc = 6a² = 6 * 1,2² cm² = 6 * 1,44 cm² = 8,64 cm²
V = a³ = 1,2³ cm³ = 1,728 cm³
c)
a = √(3/2) cm
Pc = 6a² = 6 * (√3/2)² cm² = 6 * 3/2 cm² = 3 * 3 cm² = 9 cm²
V = a³ = (√3/2)³ cm³ = 3/2√(3/2) cm³ = 1,5√1,5 cm³
zad 2
1.
a = 6 cm
b = 2 cm
c = 8 cm
Pc = 2ab + (2a + 2b) * c = 2 * 6 cm * 2 cm + 8 cm(2 * 6 cm + 2 * 2 cm) =
= 24 cm² + 8 cm(12 cm + 4 cm) = 24 cm² + 96 cm² + 32 cm² = 152 cm²
V = a *b * c = 6 cm * 2 cm * 8 cm = 96 cm³
2.
a = 1/2 cm
b = 6 cm
c = 3 cm
Pc = 2ab + c(2a + 2b) = 2 cm * 1/2 cm * 6 cm + 3 cm(2 * 1/2 cm + 2 * 6 cm) =
= 2 cm * 3 cm + 3 cm * 1 cm + 3 cm * 12 cm = 6cm² + 3cm² + 36cm² = 45cm²
V = abc = 1/2 cm * 6 cm * 3 cm = 9 cm³