Odpowiedź:
zad3
a = 9 [j]
α = 30°
[j] - znaczy właściwa jednostka
a/c = sinα = sin30°=1/2
a = c * 1/2
c =a : 1/2 = 9 : 1/2 = 9 * 2= 18 [j]
b/c = cosα = cos30° = √3/2
b = c * √3/2 = 18 * √3/2 = 9√3 [j]
β = 180° - (90° + 30°) = 180° - 120° = 60°
Odp: a = 9 [j] , b = 9√3 [j] , c = 18 [j] , α = 30° , β = 60°
zad 4
P - pole trójkąta = 1/2 * IABI * IACI * sin∡BAC = 1/2 * 8 * IACI * 11/13 = 44/13 * IACI =
= 44 cm²
44/13 IACI = 44 cm²
44IACI = 13 * 44 cm²
IACI = 13 * 44 cm²/44 cm = 13 * 1 cm =13 cm
