cos^2(70)+cos^2(40)+cos^2(50)
问题描述:
cos^2(70)+cos^2(40)+cos^2(50)
等于,打错了,中间是COS^210
答
3/2-1/2*cos40
cos^2(70)+cos^2(40)+cos^2(50)
等于,打错了,中间是COS^210
3/2-1/2*cos40