по книге Математический дивертисмент я веду кружок по геометрии и топологии для наших студентов. Например, первое занятие было про то, что неизвестна точная оценка, при каком минимальном A можно из прямоугольника 1 на A склеить лист Мёбиуса и изометрично (не растягивая и не сжимая) вложить (то есть без углов) в трёхмерное пространство. Склеиваем стороны длины 1. На картинке (из книги) показано, как сложить для для любого маленького А, если допускаются углы.
по книге Математический дивертисмент я веду кружок по геометрии и топологии для наших студентов. Например, первое занятие было про то, что неизвестна точная оценка, при каком минимальном A можно из прямоугольника 1 на A склеить лист Мёбиуса и изометрично (не растягивая и не сжимая) вложить (то есть без углов) в трёхмерное пространство. Склеиваем стороны длины 1. На картинке (из книги) показано, как сложить для для любого маленького А, если допускаются углы.
The original Telegram channel has expanded into a web of accounts for different locations, including specific pages made for individual Russian cities. There's also an English-language website, which states it is owned by the people who run the Telegram channels. He said that since his platform does not have the capacity to check all channels, it may restrict some in Russia and Ukraine "for the duration of the conflict," but then reversed course hours later after many users complained that Telegram was an important source of information. Apparently upbeat developments in Russia's discussions with Ukraine helped at least temporarily send investors back into risk assets. Russian President Vladimir Putin said during a meeting with his Belarusian counterpart Alexander Lukashenko that there were "certain positive developments" occurring in the talks with Ukraine, according to a transcript of their meeting. Putin added that discussions were happening "almost on a daily basis." If you initiate a Secret Chat, however, then these communications are end-to-end encrypted and are tied to the device you are using. That means it’s less convenient to access them across multiple platforms, but you are at far less risk of snooping. Back in the day, Secret Chats received some praise from the EFF, but the fact that its standard system isn’t as secure earned it some criticism. If you’re looking for something that is considered more reliable by privacy advocates, then Signal is the EFF’s preferred platform, although that too is not without some caveats.
from sa