求值:1/sin10°-根号3/cos10°=
问题描述:
求值:1/sin10°-根号3/cos10°=
答
1/sin10°-根号3/cos10°
=(cos10-根3*sin10)/(sin10*cos10)
=4*(sin150*cos10+sin10*cos150)/sin20
=4*sin160/sin20
=4