求(tan10°-根号3)*cos10°/sin5 - 知识问答

求(tan10°-根号3)*cos10°/sin50°的值

1个回答

(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

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