sin²(π+α)-cos(π+α)×cos(-α)+1=?

来源：学生作业帮助网编辑：作业帮时间：2024/05/14 01:35:56

sin²(π+α)-cos(π+α)×cos(-α)+1=?
sin²(π+α)-cos(π+α)×cos(-α)+1=?

sin²(π+α)-cos(π+α)×cos(-α)+1=?
sin²(π+α)-cos(π+α)×cos(-α)+1
=sin²(α)+cos(α)×cos(α)+1
=sin²α＋cos²α＋1
=1+1
=2

sin²(π+α)-cos(π+α)×cos(-α)+1
=(-sina)^2-(-cosa)*cosa+1
=(sina)^2+(cosa)^2+1
=1+1
=2