Răspuns:
Explicație pas cu pas:
[tex]\bf{ \frac{ sin3\pi}{4} = \frac{sin\pi}{4} = \frac{0}{4} = \boxed{\bf 0} }[/tex]
[tex]\bf{ \frac{cos3\pi}{4} = \frac{cos\pi}{4} = \frac{ - 1}{4} =\boxed{\bf - \frac{1}{4} }}[/tex]
[tex]\bf{ \frac{ cos2\pi }{3} = \boxed{\bf \frac{1}{3} }}[/tex]
[tex]\bf{ \frac{sin2\pi}{3} = \frac{0}{3} =\boxed{\bf 0} }[/tex]
Bafta ! :)
