Question

arcul mic AB al unui cerc de raza 6√3 cm are masura de 90 grade. aflati lungimea coardei [AB].

Answer 1

$m_{\smile AB}=m\angle\alpha=90^o \\ R=6\sqrt3 \ cm \\ l_{AB}-? \\ \bold{{l_C=2R \sin \frac{ \alpha }{ 2 }}} \\ l_{AB}=2 \cdot 6\sqrt{3} \ cm \cdot \sin\frac{90^o}{2}=12\sqrt3 \ cm\cdot\sin45^o=12\sqrt3 \ cm \cdot \frac{\sqrt2}{2} \\ \Rightarrow \boxed{\bold{l_{AB}=6\sqrt6 \ cm}}$

Answer 2

Lungimea coardei [AB] = ...