题目

满足cosα·cosβ=-sinαsinβ的一组α、β的值是(    ) A.α=,β=                   B.α=,β=C.α=,β=                        D.α=,β= 答案：解析:由已知得cosα·cosβ+sinαsinβ=.∴cos(α-β)=,因此只有A项中两角满足条件.答案:A— How do you like the program The Voice of China?—______ amazing program it is! Many people like to watch it.A. What a B. How C. What an D. How an