来自陆洪毅的问题
已知sinx-siny=-23,cosx-cosy=23,且x,y为锐角,则sin(x+y)的值是()A.1B.-1C.13D.12m]
已知sinx-siny=-23,cosx-cosy=23,且x,y为锐角,则sin(x+y)的值是()
A.1
B.-1
C.13
D.12
m]
1回答
2020-06-25 00:17
已知sinx-siny=-23,cosx-cosy=23,且x,y为锐角,则sin(x+y)的值是()A.1B.-1C.13D.12m]
已知sinx-siny=-23,cosx-cosy=23,且x,y为锐角,则sin(x+y)的值是()
A.1
B.-1
C.13
D.12
m]
∵sinx-siny=-23