若(cos2x)/[sin(x-π/4)]=-√2/2,则cosx+sinx的值为______

若(cos2x)/[sin(x-π/4)]=-√2/2,则cosx+sinx的值为______
若(cos2x)/[sin(x-π/4)]=-√2/2,则cosx+sinx的值为______

若(cos2x)/[sin(x-π/4)]=-√2/2,则cosx+sinx的值为______
(cosx^2-sinx^2)/(sinx-cosx)=1,cosx+sinx=-1