Question

Por favor preciso de ajuda!
Opção de resposta:

( ) (C)
( ) (B)
( ) (D)
( ) (E)
( ) (A)

Answer 1

$sen(105) + cos(75) \\ \\ \\ \dfrac{ \sqrt{3} - 1 }{2 \sqrt{2}} + \dfrac{1 + \sqrt{3}}{2 \sqrt{2}} \\ \\ \\ \dfrac{ -\sqrt{2} + \sqrt{6} }{4} + \dfrac{ \sqrt{2}+ \sqrt{6}}{4} \\ \\ \\ \\ => \dfrac{ \sqrt{6}}{2}$



Resposta letra a)   $\dfrac{ \sqrt{6}}{2}$

Answer 2

$sen 105^{o} +cos 75^{o}$

$sen (45^{o}+60^{o}) +cos (30^{o} +45^{o})$

$sen45^{o}.cos60^{o}+sen60^{o}.cos45^{o}+cos30^{o}.cos45^{o}-sen30^{o}.sen45^{o}$

$\dfrac{ \sqrt{2} }{2} . \dfrac{1}{2} + \dfrac{ \sqrt{3} }{2} . \dfrac{ \sqrt{2} }{2} + \dfrac{ \sqrt{3} }{2} . \dfrac{ \sqrt{2} }{2} - \dfrac{1}{2} . \dfrac{ \sqrt{2} }{2}$

$\dfrac{ \sqrt{2} }{4} + \dfrac{ \sqrt{6} }{4} + \dfrac{ \sqrt{6} }{4} - \dfrac{ \sqrt{2} }{4}$

$\dfrac{ \sqrt{6} }{4} + \dfrac{ \sqrt{6} }{4}$

$\dfrac{2 \sqrt{6} }{4}$

$\dfrac{\sqrt{6} }{2}$