(tan10°-根号3)cos10°÷sin50°
=(sin10°-根号3cos10°)÷sin50°
=2(1/2sin10°-1/2根号3cos10°)÷sin50°
=-2(sin60°cos10°-cos60°sin10°)÷sin50°
=-2sin50°÷sin50°
=-2据说不对啊。。谁敢说不对！！