Question

sin 10grade+ sin 30 grade- sin 170 grade=$\frac{1}{2}$

Answer 1

sin 10grade + sin 30grade - sin (180-10)grade = sin 10grade + sin 30grade - sin 10grade = sin 30grade = 1/2
Am aplicat reducerea la primul cadran, adica formula : sin (180-α) = sin α