Решение:
Сторона:
c = √a2 + b2 - 2ab·cos(γ°)
= √3.52 + 3.52 - 2·3.5·3.5·cos(40°)
= √12.25 + 12.25 - 24.5·0.766
= √5.733
= 2.394
Угол:
α° = arcsin(
sin(γ°))
= arcsin(
sin(40°))
= arcsin(1.462·0.6428)
= 70.01°
или:
α° = arccos(
)
= arccos(
3.52+2.3942-3.52
2·3.5·2.394
)
= arccos(
12.25+5.731236-12.25
16.76
)
= 70°
Угол:
β° = arcsin(
sin(γ°))
= arcsin(
sin(40°))
= arcsin(1.462·0.6428)
= 70.01°
Периметр:
P = a + b + c
= 3.5 + 3.5 + 2.394
= 9.394
Площадь:
p =
S =√p·(p-a)·(p-b)·(p-c)
=√4.697·(4.697-3.5)·(4.697-3.5)·(4.697-2.394)
=√4.697 · 1.197 · 1.197 · 2.303
=√15.498968619519
= 3.937
Высота :
ha =
=
= 2.25
hb =
=
= 2.25
hc =
=
= 3.289