已知cos(a-b\2)=-1\9,sin(a\2-b)=2\3,且0
问题描述:
已知cos(a-b\2)=-1\9,sin(a\2-b)=2\3,且0
答
∵cos(a-b/2)=-1/9,
0
已知cos(a-b\2)=-1\9,sin(a\2-b)=2\3,且0
∵cos(a-b/2)=-1/9,
0