10sin*7п/6* cos(-5п/4)*tg(-3п/4)
10sin(7п/6)* cos(-5п/4)*tg(-3п/4)=10sin(π+п/6)* cos(π+п/4)*tg(-π+п/4)= =10(-sin(п/6))*(- cos(п/4))*tg(п/4)=10·(1/2)·(√2)/2·1=5·(√2)/2