来自汪小飞的问题
2cos(A+B)/2*sin(A-B)/2*2sin(A+B)/2*cos(A-B)/2=sinBsinC怎么化简成sin(A+B)*sin(A-B)=sinBsinC
2cos(A+B)/2*sin(A-B)/2*2sin(A+B)/2*cos(A-B)/2=sinBsinC怎么化简成sin(A+B)*sin(A-B)=sinBsinC
1回答
2020-06-03 18:22