Предмет: Алгебра, автор: человек1681

ПОМОГИТЕ ОЧЕНЬ СРОЧНО НУЖНО!!! ПОЖАААЛУЙСТА Даны координаты точек А (1;3) В(4;1) С(3;-2) Найти угол между медианой АД и высотой АЕ. ну пожалуйста...

Ответы

Автор ответа: anna2501v
2
Оформила. Еле поместилось решение на один листок. Пользуйся)
Приложения:
человек1681: спасибо большое
au456: Кошмар то какой ) а вдруг неправильно? Как такое старание то на исправление отправлять ? )
человек1681: что???????
au456: Слишком много вычислений )
au456: Для такой простой задачи ...
человек1681: реши тогда мне ее плиз,раз простая
au456: Щас попробую )
человек1681: спасибооо
человек1681: заранее
au456: Правильно! Извините!
Автор ответа: au456
1
Координаты точки D (3.5;-0.5)
Вектор АD (2.5; -3.5) Длина √(2.5^2+3.5^2)=√74/2

Вектор СВ(1;3)
Перпендикуляр к нему (-3;1) его длина √(1+9)= √10

Косинус угла между АD и этим перпендикуляром
|2.5*(-3)-3.5|/√10/(√74/2)=22/√740=11/√185=11√185/185
Синус угла равен √(1-соs^2)=8√185/185 Тангенс = синус/косинус = 8/11
человек1681: пожалуйста
anna2501v: Я уже предоставила решение.
человек1681: ладно,спасибо....(
человек1681: мне надо будет составить уравнение прямой АЕ? потом что нужно чтобы найти угол?
anna2501v: Чтобы найти угол нужно воспользоваться одним из вариантов : 1) теорема косинусов, 2) скалярное произведение векторов, 3) соs, sin, tg или ctg в прямоугольном треугольнике.
человек1681: вы сказали если составлю уравнение прямой АЕ то найду координаты точки Е,если я найду координаты точки Е потом не смогу найти угол только по вышепредоставленным способам можно найти? смысл нам тогда искать Е и составлять уравнение АЕ?
anna2501v: Если найдешь координаты Е, то сможешь найти АЕ и ДЕ. А зная АЕ можно применять теорему косинусов
anna2501v: Зная АЕ и ДЕ
человек1681: а это уравнение сложно составлять?
anna2501v: Что бы составить уравнение прямой нужно знать координаты двух точек, принадлежащих этой прямой. Координаты одной точки есть (это точка А), а вот координаты второй нет. Сложно!
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