Question

TRIGONOMETRIA
Como agir com o 8cos²135°?


Estou sem gabarito :/

Answer 1

Sen 150° = Sen 30° = 1 / 2

Cos²135 = Cos²45° = ( - √ 2 / 2 )² = 2 / 4 = 1 / 2

Tg 45° = 1

Tg 135° = tg 45° = - 1

$\mathsf{Y = \frac{2sen150\º+cos^2135\º + tg45\º}{2sen30\º-tg135\º}} \\ \\ \\ \mathsf{Y= \frac{ \frac{2}{2}+ \frac{8}{2}+1}{ \frac{2}{2}+1 }} \\ \\ \\\mathsf{ Y= \frac{ \frac{12}{2}}{ \frac{4}{2}}} \\ \\ \\\mathsf{ Y= \frac{12}{\not2}* \frac{\not2}{4} } \\ \\ \\\mathsf{ Y= \frac{12}{4} } \\ \\ \\\boxed{\mathsf{ Y=3}}$

Bons estudos!