Все рёбра треугольной пирамиды равны. Найти угол наклона:
а) Бокового ребра к плоскости основы.
б) боковой грани к площине основы/
Объяснение:
АВСМ -пирамида, пусть ребро равно х.
a)Угол наклона бокового ребра к плоскости основания это ∠МАО.
Т.к АВ=ВС=АС, то высота проецируется в центр основания О , точку пересечения медиан.Тогда АО=2/3*АН, где АН медиана, ВН=х/2 .
Из ΔАВН-прямоугольного, АН=√(х²-х²/4)=(х√3)/2. Тогда АО=( х√3)/3.
ΔАОМ-прямоугольный, cos∠МАО=АО/АМ , cos∠МАО=( х√3)/3:х=√3/3,
∠МАО=arccos(√3/3) .
ОМ=√(х²-( х√3)/3)² )=(х√6)/3
б)В равностороннем ΔАВС , медиана АН является высотой . Тогда МН⊥ВС по т. о трех перпендикулярах и ∠АНМ-линейный угол между боковой гранью и плоскостью основания.
ОН=1/3*АН , ОН=(х√3)/6.
ΔОНМ-прямоугольный ,tg∠AHM=MO/OH , tg∠AHM=2√2 , ∠AHM=arctg(2√2).
You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England and you really start liking this county. Write this news to your English friend: a) The more I read about England, the bigger I like it. 6) The much I read about England, the bigger I like B) The more I read about England, the more I like it. r) The many I read about England, the many I like it. You read a lot about England an
