【正文】
co ss i nt an ??????xy? ?4,30 ??P0MOyxM? ?yxP ,題型二:已知角終邊上點的坐標(biāo),求三角函數(shù)值 ? ? ? ? ? ? ?????? ??611t a n3。49c o s2。7 8 0s i n1??? ?224c o s)24c o s (49c o s2 ???? ????? ?336t a n)26t a n ()611t a n (3 ????? ????解: ? ?)360260s i n (780s i n1 ???????? 60s in23?題型三 :求下列三角函數(shù)值: