求1/sin10°-根号3/cos10°的值(要过程)
问题描述:
求1/sin10°-根号3/cos10°的值(要过程)
答
1/sin10°-(根号3)/cos10° =(cos10°-(根号3)sin10°)/(sin10°×cos10°) =2(1/2 cos10°- (根号3)/2 sin10°))/(sin10°×cos10° =2(sin30°cos10°-cos30°sin10°)/(sin10°×cos10°) =2sin20°/(sin10°×co...