Question

срочна  помогите))
sin$frac{7 pi }{12}$ + sin$frac{5 pi }{12}$

Answer 1

 $sinfrac{7pi}{12}+sinfrac{5pi}{12}=2sinfrac{frac{7pi}{12}+frac{5pi}{12}}{2}cosfrac{frac{7pi}{12}-frac{5pi}{12}}{2}=2sinfrac{pi}{2} cosfrac{pi}{12}=2cosfrac{pi}{12}$