Предмет: Математика, автор: geinlove924

Длина окружности 47,1 м. Найдите площадь круга, ограниченного этой окружностью. (Число пи=3,14)

Ответы

Автор ответа: Gregorj

формула для нахождения радиуса круга С = 2 пи × r. Поэтому r = 2C / пи. Формула для нахождения площади круга S = пи × r^2, значит S = пи × ( 2С / пи )^2, значит S = пи × 4С^2 / пи^2 = 4С^2 / пи = 4 × 47,1^2 / 3,14 = 2826
Ответ: 2826

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