已知(1+sinx+cosx)/(1+sinx-cosx)=1/2,则tanx/2的值等于?
问题描述:
已知(1+sinx+cosx)/(1+sinx-cosx)=1/2,则tanx/2的值等于?
答
(1+sinx+cosx)/(1+sinx-cosx)
=[2sin(x/2)cos(x/2)+2cos(x/2)cos(x/2)]/2sin(x/2)cos(x/2)+2sin(x/2)sin(x/2)]
=tan(x/2)=1/2