(1/sin10)-(√3/cos10)
问题描述:
(1/sin10)-(√3/cos10)
答
1/sin10°)-(√3)/cos10° =(cos10°)-(√3)sin10°)/(sin10°×cos10°) =2(1/2 cos10°-(√3)/2 sin10°))/(sin10°×cos10° =2(sin30°cos10°-cos30°sin10°)/(sin10°×cos10°) =2sin20°/(sin10°×cos10°...