Ответ :
[tex] \sin(15) \times \cos(15) = \frac{1}{2} \times 2 \sin(15) \times \cos(15) = \frac{1}{2} \times \sin(30) = \frac{1}{4} [/tex]
sin2a=2sina×cosa
[tex] \sin(15) \times \cos(15) = \frac{1}{2} \times 2 \sin(15) \times \cos(15) = \frac{1}{2} \times \sin(30) = \frac{1}{4} [/tex]
sin2a=2sina×cosa