sin50(1 √3tan10)等于多少
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有点难度的高中数学题，请大家指教
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sin50(1+√3tan10)=sin50(1+tan(60)tan10))=sin50(1+sin(60)sin10)/[cos(60)cos(10])=sin(50)[sin60sin10+cos60cos10]/[cos60cos10]=sin(50)cos(60-10)/[cos(60)cos(10)]=sin(50)cos(50)/[cos(60)cos(10)]=sin(100)/[2cos(60)cos(10)]=sin(100)/cos(10)=cos(10)/cos(10)=1
