题目

tanx=1,3sinb=sin(2x+b),求tan(x+b)

提问时间：2021-01-03

答案

3sin(x+b-x)=sin(x+b)cosx+cos(x+b)sinx 3sin(x+b)cosx-3cos(x+b)sinx=sin(x+b)cosx+cos(x+b)sinx 2sin(x+b)cosx=4cos(x+b)sinx tan(x+b)=2tanx=2