tan0,tan0等于多少

将arctanz在z0=0展开为泰勒级数
arctan1 arctan0是等于多少?
当x接近于0时,求(tan3x)/x的极限
6,cos36.5°=0.8,tan36.5°=0.75,sin23.6°=0.4,cos66.4°=0.
解: = - '=40 pp'=100tan0 0 40 =0.