恒等变换中的话,推荐这道题
求(tan10°-根号3)*cos10°/sin50°的值
(tan10°-√3)*cos10°/sin50°
=(sin10°-√3cos10°)/sin50°
=2(1/2*sin10°-√3/2*cos10°)/sin50°
=2(sin10°cos60°cos10°sin60°)/sin50°
=2sin(10-60)°/sin50°
=2sin(-50)°/sin50°
=-2sin50°/sin50°
=-2
恒等变换中的话,推荐这道题
求(tan10°-根号3)*cos10°/sin50°的值
(tan10°-√3)*cos10°/sin50°
=(sin10°-√3cos10°)/sin50°
=2(1/2*sin10°-√3/2*cos10°)/sin50°
=2(sin10°cos60°cos10°sin60°)/sin50°
=2sin(10-60)°/sin50°
=2sin(-50)°/sin50°
=-2sin50°/sin50°
=-2