Двойной интеграл с парой трюков и красивым ответом

In this video, we'll find a double integral with the hyperbolic cosine and arccosine functions. This is a telling example demonstrating how dramatically an integral can change when changing the variable and the order of integration. Playlist with double, triple, and surface integrals:    • Двойные, тройные, поверхностные интегралы   If you can, support the channel: Sberbank: 4276160020048840 Tinkoff: 5536914075973911 Regular support: https://boosty.to/hmath