Задача. Пусть 𝐼 — центр вписанной окружности остроугольного треугольника 𝐴𝐵𝐶. Точки 𝑃, 𝑄, 𝑅 выбраны на сторонах 𝐴𝐵, 𝐵𝐶, 𝐶𝐴 соответственно так, что 𝐴𝑃 = 𝐴𝑅 и 𝐵𝑃 = 𝐵𝑄, и ∠𝑃𝐼𝑄 =∠𝐵𝐴𝐶. Докажите, что 𝑄𝑅 ⊥ 𝐴𝐶.
В международный день гор, желаем вам достигнуть новых высот 🪜
Задача. Пусть 𝐼 — центр вписанной окружности остроугольного треугольника 𝐴𝐵𝐶. Точки 𝑃, 𝑄, 𝑅 выбраны на сторонах 𝐴𝐵, 𝐵𝐶, 𝐶𝐴 соответственно так, что 𝐴𝑃 = 𝐴𝑅 и 𝐵𝑃 = 𝐵𝑄, и ∠𝑃𝐼𝑄 =∠𝐵𝐴𝐶. Докажите, что 𝑄𝑅 ⊥ 𝐴𝐶.
В международный день гор, желаем вам достигнуть новых высот 🪜
"There are a lot of things that Telegram could have been doing this whole time. And they know exactly what they are and they've chosen not to do them. That's why I don't trust them," she said. Founder Pavel Durov says tech is meant to set you free "Russians are really disconnected from the reality of what happening to their country," Andrey said. "So Telegram has become essential for understanding what's going on to the Russian-speaking world." Two days after Russia invaded Ukraine, an account on the Telegram messaging platform posing as President Volodymyr Zelenskiy urged his armed forces to surrender. Now safely in France with his spouse and three of his children, Kliuchnikov scrolls through Telegram to learn about the devastation happening in his home country.
from fr