Предмет: Математика, автор: ValikMazyr

Длины двух окружностей относятся как 4 : 9.
Как относятся площади кругов, ограниченных этими окружностями?​

Ответы

Автор ответа: TinaKasper
0

Ответ:

Площадь круга равна S=πr²

Длина окружности равна L=2πr

Отсюда следует, что r=\frac{2}{L}π

S=π²\frac{4}{L^{2} }

Пусть L₁=4k, L₂=9k

Тогда,

\frac{\pi ^{2} *\frac{4}{16k^{2} }}{\pi ^{2} *\frac{4}{81k^{2} }} \\\\\\\frac{4}{16k^{2} } :\frac{4}{81k^{2} } =\frac{81}{16}

Ответ: 81:16

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The banks of Sacramento (by J. London)
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