计算：sin25π/6+cos25π/4+tan(-25π/4)+sin(-26π/3)
问题描述：
计算：sin25π/6+cos25π/4+tan(-25π/4)+sin(-26π/3)
答
原式=sin(4π+π/6)+cos(6π+π/4)-tan(6π+π/4)-sin(8π+2π/3)
=sinπ/6+cosπ/4-tanπ/4-sin2π/3
=1/2+√2/2-1-√3/2
=（√2-√3-1）/2