3π 3 5. (2011· 重庆高考)若 cos α=- , α∈ π, 2 , tan α 且 则 5
=________.
4 解析:依题意得 sin α=- 1-cos α=- , 52
sin α 4 tan α= = . cos α 3
4 答案: 3
3π 3 5. (2011· 重庆高考)若 cos α=- , α∈ π, 2 , tan α 且 则 5
=________.
4 解析:依题意得 sin α=- 1-cos α=- , 52
sin α 4 tan α= = . cos α 3
4 答案: 3