设集合M={y|y=|cos^2-sin^2|,x属于R},N={x||x-(1/i)|

问题描述:

设集合M={y|y=|cos^2-sin^2|,x属于R},N={x||x-(1/i)|设集合M={y|y=|cos^2-sin^2|,x属于R},N={x||x-(1/i)|A.(0.1)B.(0.1]C.[0.1)D.[0.1]

y=|cos^2 x-(1-cos^2 x)|=|2cos^2 x-1|,
-1