Решение:
Сторона:
c = √a2 + b2 - 2ab·cos(γ°)
= √802 + 802 - 2·80·80·cos(45°)
= √6400 + 6400 - 12800·0.7071
= √3749.1
= 61.23
Угол:
α° = arcsin(
sin(γ°))
= arcsin(
sin(45°))
= arcsin(1.307·0.7071)
= 67.54°
или:
α° = arccos(
)
= arccos(
)
= arccos(
6400+3749.1129-6400
9796.8
)
= 67.5°
Угол:
β° = arcsin(
sin(γ°))
= arcsin(
sin(45°))
= arcsin(1.307·0.7071)
= 67.54°
Периметр:
P = a + b + c
= 80 + 80 + 61.23
= 221.23
Площадь:
p =
S =√p·(p-a)·(p-b)·(p-c)
=√110.62·(110.62-80)·(110.62-80)·(110.62-61.23)
=√110.62 · 30.62 · 30.62 · 49.39
=√5122512.8087399
= 2263.3
Высота :
ha =
=
= 56.58
hb =
=
= 56.58
hc =
=
= 73.93