Câu hỏi:

\[ - \frac{\pi }{2} + k2\pi ,k \in \mathbb{Z}\]

\[ - \frac{{3\pi }}{2} + k2\pi ,k \in \mathbb{Z}\]

\[\pi + k2\pi ,k \in \mathbb{Z}\]

\[\frac{\pi }{2} + k2\pi ,k \in \mathbb{Z}\]

\( - \frac{1}{3}.\)

\(\frac{2}{3}.\)

\( - \frac{2}{3}.\)

\(\frac{1}{3}.\)

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

\(\left( {\frac{{3\pi }}{2};\frac{{5\pi }}{2}} \right)\)

\(\left( { - \frac{{3\pi }}{2}; - \frac{\pi }{2}} \right)\)

\(\left( { - 3\pi ; - 2\pi } \right)\)

\(x = \frac{\pi }{4} + k\pi {\rm{ }}\left( {k \in \mathbb{Z}} \right)\)

\(x = \frac{\pi }{4} + k2\pi {\rm{ }}\left( {k \in \mathbb{Z}} \right)\)

\(x = \frac{\pi }{2} + k2\pi {\rm{ }}\left( {k \in \mathbb{Z}} \right)\)

\(x = \frac{{k\pi }}{2}{\rm{ }}\left( {k \in \mathbb{Z}} \right)\)

\({u_5} = \frac{{17}}{{12}}.\)

\({u_5} = \frac{{71}}{{39}}.\)

\({u_5} = \frac{7}{4}.\)

\({u_5} = \frac{1}{4}.\)

\(d = - 2\)

\(d = 1\)

\(d = 3\)

\(d = 2\)

\({u_n} = \frac{1}{n}\)

\({u_n} = 3n\)

\({u_n} = {2^n} + 1\)

\({u_n} = {2^n}\)

\(25\)

\(26\)

\(27\)

\(28\)

\[{M_o} = \frac{{50}}{3}\]

\[{M_o} = \frac{{70}}{3}\]

\[{M_o} = \frac{{70}}{2}\]

\[{M_o} = \frac{{80}}{3}\]

\(\frac{{4\sqrt 2 }}{7}\)

\(\frac{{\sqrt 5 }}{2}\)

\( - \frac{{4\sqrt 2 }}{7}\)

\( - \frac{{\sqrt 5 }}{2}\)