cos10°+cos110°-cos50°=
1个回答
cos10°+cos110°-cos50°
=2cos60°cos50°-cos50°
=cos50°-cos50°
=0
相关问题
sin10°cos50°+sin50°cos10°
sin100°cos 110° cos100°sin110°
请证明(sin10)(cos10)(cos30)(cos50)(cos70)=(3/16)*(cos80),thx la
sin10加sin50除以cos10加cos50
sin10°cos50°+sin50°cos10°的三角函数值
急求三角函数cos10°cos50°cos70°的值.
sin40°cos110°+cos40°sin110°的值
(sin50°(1+√3tan10°)-cos20°)/cos80°√(1-cos20°
求值cos70cos50+(sin10)^2 (70,50,10表示角度):cos40(1+tan60tan10) (4
sin20°sin110°-cos160°cos70°