Задача. Дан равнобедренный треугольник 𝐴𝐵𝐶 (𝐴𝐵 = 𝐴𝐶). Пусть 𝑋 — произвольная точка прямой 𝐵𝐶, не совпадающая с 𝐵 и 𝐶. Точки 𝑃 и 𝑄 — проекции 𝑋 на 𝐴𝐵 и 𝐴𝐶 соответственно. Докажите, что описанные окружности треугольников 𝐴𝐵𝑄 и 𝐴𝐶𝑃 пересекаются на прямой 𝐴𝑋.
Задача. Дан равнобедренный треугольник 𝐴𝐵𝐶 (𝐴𝐵 = 𝐴𝐶). Пусть 𝑋 — произвольная точка прямой 𝐵𝐶, не совпадающая с 𝐵 и 𝐶. Точки 𝑃 и 𝑄 — проекции 𝑋 на 𝐴𝐵 и 𝐴𝐶 соответственно. Докажите, что описанные окружности треугольников 𝐴𝐵𝑄 и 𝐴𝐶𝑃 пересекаются на прямой 𝐴𝑋.
"For Telegram, accountability has always been a problem, which is why it was so popular even before the full-scale war with far-right extremists and terrorists from all over the world," she told AFP from her safe house outside the Ukrainian capital. The gold standard of encryption, known as end-to-end encryption, where only the sender and person who receives the message are able to see it, is available on Telegram only when the Secret Chat function is enabled. Voice and video calls are also completely encrypted. Pavel Durov, Telegram's CEO, is known as "the Russian Mark Zuckerberg," for co-founding VKontakte, which is Russian for "in touch," a Facebook imitator that became the country's most popular social networking site. In a message on his Telegram channel recently recounting the episode, Durov wrote: "I lost my company and my home, but would do it again – without hesitation." The Dow Jones Industrial Average fell 230 points, or 0.7%. Meanwhile, the S&P 500 and the Nasdaq Composite dropped 1.3% and 2.2%, respectively. All three indexes began the day with gains before selling off.
from jp
