sin40°（tan10°-√3）=sin40°(sin10°/cos10°-√3)=sin40°(sin10°-√3cos10°)/cos10°=2sin40°[sin10°cos60°-cos10°sin60°]/cos10°=2sin40*sin(-50°)/cos10°=-2sin40°cos40°/cos10°=-sin80°/cos1...