Question

(20 PONTOS) Simplifique:

$E=\dfrac{\sec x\cdot \sec y}{1+\mathrm{tg\,}x\cdot \mathrm{tg\,}y}$

Answer 1

$E= \frac{ \frac{1}{cos(x)}* \frac{1}{cos(y)} }{1+ \frac{sen(x)}{cos(x)}* \frac{sen(y)}{cos(y)} } \\\\E= \frac{1}{cos(x)*cos(y)} * \frac{cos(x)*cos(y)}{cos(x)*cos(y)+sen(x)*sen(y)} \\\\ E= 1* \frac{1}{cos(x-y)}=sec(x-y)$

Answer 2

 A resposta segue anexa. 

*-*-*-*-*-*-*-*-*-*-*-*
17/02/2016 
Sepauto - SSRC
*-*-*-*-*-*-*-*-*-*-*-*