2020年中考数学要点：三角函数积化和差公式

sincosplay=(1/2)[sin(+)+sin(-)]cosplaysin=(1/2)[sin(+)-sin(-)]cosplaycosplay=(1/2)[cosplay(+)+cosplay(-)]新初中三年级快扫描二维码关注中考网公众号每天推送学习方法，学科要点帮你迎接2020年中考！sinsin=-(1/2)[cosplay(+)-cosplay(-)]sincosplay=(1/2)[sin(+)+sin(-)]cosplaysin=(1/2)[sin(+)-sin(-)]cosplaycosplay=(1/2)[cosplay(+)+cosplay(-)]sinsin=-(1/2)[cosplay(+)-cosplay(-)]