求特殊角的正弦余弦值

X 30 45 60 90 120 150 180 y=sinx 1/2 √2/2 √3/2 1 √3/2 1/2 0y=cosx √3/2 √2/2 1/2 0 -1/2 -√3/2 -1X 7π/6 4π/3 3π/2 5π/3 11π/6y= -1/2 -√3/2 -1 -√3/2 -1/2 y= -√3/2 -1/2 0 1/2 √3/2 其他的根据...我就是懒得算才让你们帮我算的，麻烦了sin15°=sin(45°-30°)=sin45cos30-cos45sin30=√2/2*√3/2-√2/2*1/2=(√6-√2)/4sin75°=sin(45°+30°)=sin45cos30+cos45sin30=√2/2*√3/2+√2/2*1/2=(√6+√2)/4sin105°=sin(180°-75°)=sin75°=(√6+√2)/4cos15°=sin(90°-15°)=sin75°=(√6+√2)/4cos75°=sin(90°-75°)=sin15°=(√6-√2)/4cos105°=cos(90°-(-15°))=sin(-15°)=-sin15°=(√2-√6)/4