Resposta :
sen 0 = 0
sen (pi/2) = 1
sen (3pi/2) = - 1
sen(pi/6) = 1/2
y = (0 + 1 - 1)/[2(1/2)] = 0
y = 0
sen (pi/2) = 1
sen (3pi/2) = - 1
sen(pi/6) = 1/2
y = (0 + 1 - 1)/[2(1/2)] = 0
y = 0