Решение:
Угол:
γ° = arcsin(
sin(α°))
= arcsin(
sin(45°))
= arcsin(0.5·0.7071)
= 20.7°
Угол:
β° = 180 - γ° - α°
= 180 - 20.7° - 45°
= 114.3°
Сторона:
b = √a2 + c2 - 2ac·cos(β°)
= √82 + 42 - 2·8·4·cos(114.3°)
= √64 + 16 - 64·-0.4115
= √106.34
= 10.31
или:
b = a·
= 8·
= 8·
= 8·1.289
= 10.31
или:
b = c·
= 4·
= 4·
= 4·2.578
= 10.31
Высота :
hc = a·sin(β°)
= 8·sin(114.3°)
= 8·0.9114
= 7.291
Периметр:
P = a + b + c
= 8 + 10.31 + 4
= 22.31
Площадь:
p =
S =√p·(p-a)·(p-b)·(p-c)
=√11.16·(11.16-8)·(11.16-10.31)·(11.16-4)
=√11.16 · 3.16 · 0.85 · 7.16
=√214.6264416
= 14.65
Высота :
ha =
=
= 3.663
hb =
=
= 2.842