化简[sin(2A+B)]/sinA-2cos(A+B)
来源：学生学帮网 编辑：学帮网 时间：2024/06/01 08:09:43
化简[sin(2A+B)]/sinA-2cos(A+B)
[sin(2A+B)]/sinA-2cos(A+B)
=[sin(A+B+A)]/sinA-2cos(A+B)
=[sin(A+B)cosA+cos(A+B)sinA]/sinA-2cos(A+B)
=[sin(A+B)cosA-cos(A+B)sinA]/sinA
=sin(A+B-A)/sinA
=sinB/sinA