化简:二分之一cos105°+二分之根号三sin105°
问题描述：
化简:二分之一cos105°+二分之根号三sin105°
答
=sin30°cos105°+cos30°sin105°
=sin(30°+105°)
=sin135°
=√2/2
答
(1/2)cos105°+(√3/2)sin105°.
=sin30°cos105°+cos30sin105°.
=sin(30°+105°).
=sin135°.
∴ 原式=√2/2,