Решение:
Угол:
α° = arccos(
)
= arccos(
)
= arccos(
)
= 80.28°
Периметр:
P = a + b + c
= 20 + 15 + 16
= 51
Площадь:
p =
S =√p·(p-a)·(p-b)·(p-c)
=√25.5·(25.5-20)·(25.5-15)·(25.5-16)
=√25.5 · 5.5 · 10.5 · 9.5
=√13989.9375
= 118.28
Высота :
ha =
=
= 11.83
hb =
=
= 15.77
hc =
=
= 14.79
Угол:
β° = arcsin(
sin(α°))
= arcsin(
sin(80.28°))
= arcsin(0.75·0.9856)
= 47.66°
Угол:
γ° = arcsin(
sin(α°))
= arcsin(
sin(80.28°))
= arcsin(0.8·0.9856)
= 52.04°