Решение:
Угол:
α° = arccos(
)
= arccos(
67502+78002-100002
2·6750·7800
)
= arccos(
45562500+60840000-100000000
105300000
)
= 86.51°
Периметр:
P = a + b + c
= 10000 + 6750 + 7800
= 24550
Площадь:
p =
S =√p·(p-a)·(p-b)·(p-c)
=√12275·(12275-10000)·(12275-6750)·(12275-7800)
=√12275 · 2275 · 5525 · 4475
=√6.9044362460938E+14
= 26276294
Высота :
ha =
=
= 5255.3
hb =
=
= 7785.6
hc =
=
= 6737.5
Угол:
β° = arcsin(
sin(α°))
= arcsin(
sin(86.51°))
= arcsin(0.675·0.9981)
= 42.35°
Угол:
γ° = arcsin(
sin(α°))
= arcsin(
sin(86.51°))
= arcsin(0.78·0.9981)
= 51.13°