Question

Am nevoie sa arat ca sin 5pi/6 = 1/2 ! Materie clasa a10a !

Answer 1

sin (5π/6)=sin(π-5π/6)=sinπ/6=1/2
 as simple as that!

Answer 2

[tex]\it \dfrac{5\pi}{6} =\dfrac{5\cdot 180^o}{6} = 5\cdot30^o =150^o \\\;\\ \\\;\\ sin 150^o=sin(180^o-150^o) = sin30^o =\dfrac{1}{2}[/tex]

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$\it sin\dfrac{5\pi}{6} = sin\dfrac{6\pi-\pi}{6} = sin\left(\pi-\dfrac{\pi}{6}\right) =sin\dfrac{\pi}{6} = \dfrac{1}{2}$