化简cos(45°-α)-sin(45°+α),得
-cos(α-45°)=sin(α+45°)对吗?
化简:(5)cos(α-45°)cos(15°+α)+sin(α-45°)sin(15°+α)
化简cos^2(-α)-[tan(360°+α)/sin(-α)]
化简,cos²(-α)-tan(360°+α)/sin(-α)
化简cos(540°-α)sin(α-360°)/sin(-α+180°)cos(180°+α)
化简cos(α+30°)cos(α-30°)-sin(α+30°)sin(α+150°),
化简cos(15°+a)sin(45°+a)-cos(75°-a)sin(45°-a)
已知sinα•cosα=18,且0°<α<45°,则cosα-sinα的值为( )
若sinα+cosα=m,则sinα-cosα=____.(0°<α<45°)
已知sinαcosα=八分之一,且0°<α<45°,求cosα-sinα的值
已知sinα×cosα=1/8,且0°<α<45°,则cosα﹣sinα=
Cos(180°+α)*sin(α+360°)/sin(-α-180°)*cos(-180°-α)