三角函数计算sin260°+cos260 (2) -tan450(3)cos45°-sin30° (4)sin2300+cos2300(5)tan45°-sin30°·cos60° (6) (7)2sin300-cos450 (6)sin600cos600 (8)2sin30°+3cos60°-4tan45° (9)cos30°sin45°+sin30°cos45° (10) cos30°+ sin45° (12)2sin300+3sin600-4tan450 (13)tan300sin450+tan600cos450 (14) (15) ;(16) =________________ (18). (19)sin230°+cos245°+ sin60°·tan45°; (20) + sin45(21) (22) (23) 24 25 (26) (27) 28 29 (30) 31 (32) 33 34 35 (36) (37) 38 39 (40) (41) (42) (43) (44) 45 46 (47) 48 |