2sin²α+3sinαcosα-cos²α

来源：学生作业帮助网编辑：作业帮时间：2024/06/04 01:57:41

化简吗?
原式=2*(1-cos2α)/2+3/2*sin2α-(1+cos2α)/2
=3/2*sin2α-3/2*cos2α+1/2
=3/2*(sin2α-cos2α)+1/2
=3√2/2*sin(2α-π/4)+1/2