sin7兀/12点算
问题描述：
sin7兀/12点算
是sin（7兀/12）点算
答
原式=sin(7π/12)
=sin105°
=sin(60°+45°)
=sin60°cos45°+cos60°sin45°
=(√3)/2×(√2)/2+1/2×(√2)/2
=(√6+√2)/4