Question

sin7п/12 -sinп/12=корень из 2/2

Answer 1

$Sin\frac{7\pi }{12}-Sin\frac{\pi }{12}=2Sin\frac{\frac{7\pi }{12}-\frac{\pi }{12}}{2} Cos\frac{\frac{7\pi }{12}+\frac{\pi }{12}}{2}=2Sin\frac{\pi }{4}Cos\frac{\pi }{3}=2*\frac{\sqrt{2} }{2}*\frac{1}{2} =\frac{\sqrt{2}}{2}$