8pi/3=8*180/3=480=360+120
sin120=корень из 3/2
25pi/4=25*180/4=1125=1080+45=6pi+45
cos(25pi/4)=cos45=корень из 2/2
умножишь все сам....
2*√6*sin(8π/3)*cos(25π/4)=3. 1) sin(8π/3)=8*180°/3=sin480°=sin(360°+120°)=sin120°=√3/2. 2) cos(25π/4)=cos(25*180°/4)=cos(25*45°)=cos1125°= =(3*360+45°)=cos45°=√2/2. 3) 2*√6*(√3/2)*(√2/2)=2*√6*√6/4=6/2=3.