3 三角函數的有關計算1.用計算器求下列各式的值: (16分)(1)sin20°; (2)cos38°; (3)tan10°; (4)tan80°; (5)co
切割化弦，整理，积化和差，可以得到sin x=0.7*sin85=0.7*cos 15 后面就是死算了 ...
【题目】21計算下列的值:(1cos135°*cos(-45°)-sin210°*tan45° =sin^218°+sin^223°+sin^267°+sin^272°= in2(3(sin(-θ))/(sin(180°+θ)-(tan(180°-θ))/(tan(180+α))= (cos(360°-θ))/(cos(180+α))= 相关知识点: ...