(2cos55-(√3)sin5)/cos5

问题描述:

(2cos55-(√3)sin5)/cos5

原式=[2cos(60-5)-√3sin5)]/cos5
=[2(1/2cos5+√3/2sin5)-√3sin5]/cos5
=(cos5+√3sin5-√3sin5)/cos5
=cos5/cos5
=1