Chọn mệnh đề đúng:

\(R\backslash \left\{ {k\pi ,k \in Z} \right\}\)

\(R\backslash \left\{ {\dfrac{{k\pi }}{2},k \in Z} \right\}\)

\(R\backslash \left\{ {\dfrac{\pi }{2} + k\pi ,k \in Z} \right\}\)

\(R\)

\(\left( { - 1;1} \right)\)           

\(\left[ { - 1;1} \right]\)

\(R\)

\(\left[ {0;1} \right]\)

\(\left( {\dfrac{\pi }{2} + k2\pi ;\dfrac{{3\pi }}{2} + k2\pi } \right)\)

\(\left( { - \pi  + k2\pi ;k2\pi } \right)\)

\(\left( {k2\pi ;\pi  + k2\pi } \right)\)                           

\(R\)

\(O\left( {0;0} \right)\)

\(M\left( {0;1} \right)\)

\(N\left( {\dfrac{\pi }{2};0} \right)\)

\(P\left( {1;0} \right)\)

\(\max y =  - 2,\min y = 4\)

\(\max y = 2,\min y = 4\)

\(\max y =  - 2,\min y = 3\)

\(\max y = 4,\min y =  - 2\)

\(\min y = \dfrac{4}{3};\max y = 4\)

\(\min y = \dfrac{4}{3};\max y = 3\)

\(\min y = \dfrac{4}{3};\max y = 2\)

\(\min y = \dfrac{1}{2};\max y = 2\)