Question

Alguém me ajuda por favor é urgente!!!!!

Answer 1

Propriedades:

• $(a+b)^2=a^2+2ab+b^2$

• $\sin^2x+\cos^2x=1$

• $\sin2a=2\sin a.\cos a$

$(\sin\alpha+\cos\alpha)^2\\\\\sin^2\alpha+2\sin\alpha.\cos\alpha+\cos^2\alpha\\\\1+\sin2\alpha\\\\1+\sin(2.\frac{13\pi}{12})\\\\1+\sin\frac{26\pi}{12}\\\\1+\sin\frac{\pi}{6}\\\\1+\frac{1}{2}\\\\\frac{2+1}{2}\\\\\frac{3}{2}$