Question

найдите длину окружности описаннтй около квадрата со стороной 5 см​

Answer 1

$C = 2\pi r$

$r = \frac{a}{\sqrt2} = \frac{5}{\sqrt 2}$

$C = 2 * 3.14 * \frac{5}{\sqrt2} = 6.28 * \frac{5}{\sqrt2} = \frac{31.4}{\sqrt2}$

$C = \frac{31.4}{\sqrt2}$