题目

已知角α的终边上一点的坐标为的最小正值为． 答案：． 【考点】三角函数的周期性及其求法． 【分析】先α的终边上一点的坐标化简求值，确定α的正余弦函数值，在再确定角α的取值范围． 【解答】解：由题意可知角α的终边上一点的坐标为（sin，cos），即（，﹣） ∴sinα=﹣，cosα=∴α=（k∈Z） 故角α的最小正值为： 故答案为： 【点评】本题主要考查 (完形填空) I love music. Young people today may not know Zhu Mingying. But I know she was very famous more than twenty years 1 . She was a dancer at first. But one day she thought that she could also sing 2 . So she went to visit a music teacher. The teacher 3 her to sing a few songs and then said that she would not be successful in singing, 4 she didn’t have a good voice. 5 Zhu Mingying didn’t give up. She spent a lot of time 6 to music lessons. She had 7 time to rest. She didn’t have much money to buy 8 delicious food. Life was really hard for her at that time. But she didn’t complain about anything. Instead, she felt happy because she proved that she could be a good singer at last 9 she practiced singing for many years. If you want to do something, just 10 . You’ll be successful in the end!(1) A.ago B.before C.later D.after [　　] (2) A.good B.better C.best D.well [　　] (3) A.asking B.asks C.asked D.to ask [　　] (4) A.so B.but C.because D.why [　　] (5) A.And B.So C.But D.When [　　] (6) A.going B.to go C.went D.gone [　　] (7) A.a little B.few C.a few D.little [　　] (8) A.herself B.hers C.him D.the teacher [　　] (9) A.before B.after C.and D.so [　　] (10) A.have music lessons B.try your best C.find a teacher D.spend little money [　　]