Предмет: Геометрия, автор: dashen73

Решите пожалуйста ) подробнее) В правильной треугольной призме ABCA1B1C1, все ребра которой равны 1, найдите расстояние между прямыми AB1 и BC1.

Ответы

Автор ответа: au456

Пусть В - начало координат

Ось X - BA

Ось Y - перпендикулярно X в сторону C

Ось Z - BB1

Вектора

BB1 ( 0;0;1)

AB1 ( -1;0;1)

BC1 ( 1/2;√3/2;1)

= | -√3/2 | / √ ( 3/4 + 9/4 + 3/4 ) = √5 / 5

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