题干
已知tanα=2，则 π
)+cos(α−π
)3sin(π
−α)−cos(π
+α) =____．
| s |
| i |
| n |
| ( |
| + |
| 2 |
| 2 |
| 2 |
| 2 |
答案(点此获取答案解析）
| 3 |
| 5 |
