sin(a-π/3)=1/3,则cos(π/6+a)=
1个回答
cos(π/6+a)
=sin[π/2-(a+π/6)]
=sin(π/3-a)
=-sin(a-π/3)
=-1/3
相关问题
若sin(π/6+a)=1/3,则cos(π/3—a)=_______,cos(2π/3+a)=________
若sin(π/6-a)=1/3,则cos(π/3+a)
sin(π/6)-a=1/3,则cos(2π/3)+2a=?
已知sin(a-π/3)=1/3,则cos(a+π/6)等于
若sin(π /6-a)=1/3,则cos(2π /3+2a)=__________
已知sin(π/3 -a)=1/2,则cos(π/6 +a)=?
sin(π/6-a)=1/3 则 cos(2/3π+2a) 等于什么?
若cos(a-π/3)=3/5 则sin(2a-π/6)=
若sin(π/6-啊)=1/3,则cos(2π/3+2a)=?
已知sin(π/6-a)=1/4,则cos(π/3-2a)=?