Question

Aria totala a unui con circular drept este de 253 cm(patrati) ,iar aria lui laterala - de 11 cm(patrati)....Aflati lungimea generatoarei conului..!))

Answer 1

$253=\pi R(G+R)$
$11=\pi R G$

Inlocuim a doua relatie in prima

$253=11+\pi \ R^2$
$242=\pi R^2$

$R=\sqrt{\dfrac{242}{\pi}}=\dfrac{11\sqrt2}{\sqrt{\pi}}$ Inlocuim in al doilea rand de sus

$G=\dfrac{11}{\pi R}=\dfrac{11}{\pi\cdot\dfrac{11\sqrt2}{\sqrt{\pi}}}=\dfrac{1}{\sqrt{2\pi}}=\dfrac{\sqrt{2\pi}}{2\pi}$