求值：sin14π3+cos(−25π4)=_．
问题描述：
求值：sin
+cos(−14π 3
)=______． 25π 4
答
sin
+cos(−14π 3
)=sin(4π+25π 4
)+cos(6π+2π 3
)=sinπ 4
+cos2π 3
=π 4
．
+
3
2
2
故答案为：
．
+
3
2
2