Câu hỏi:

\(-\sqrt{3}\)

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

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

\(\sqrt{3}\)

\(\mathbb{R}.\)

\(\mathbb{R}\backslash \left\{ \frac{\pi }{2}+k2\pi \,|\,k\in \mathbb{Z} \right\}.\)

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

\(\mathbb{R}\backslash \left\{ \frac{\pi }{2}+k\pi \,|\,k\in \mathbb{Z} \right\}.\)

A\(\frac{\pi }{1\,013}\)

\(1\,013\pi \)

\(2\pi \)

\(\pi \)

\(x=\alpha +k4\pi ,\,\left( k\in \mathbb{Z} \right)\)

\(x=\alpha -k2\pi ,\,\left( k\in \mathbb{Z} \right)\)

\(x=\alpha +k2\pi ,\,\left( k\in \mathbb{Z} \right)\)

\(x=\alpha +k\pi ,\,\left( k\in \mathbb{Z} \right)\)

\({{u}_{n}}=\sqrt{{{n}^{2}}+1}\)

\({{u}_{n}}=\frac{5n-2}{3}\)

\({{u}_{n}}=\frac{2}{n+1}\)

\({{u}_{n}}={{3}^{n+1}}\)

\(1;\,\frac{2}{3};\,\frac{3}{7};\,\frac{4}{15};\,\frac{5}{32}\)

\(1;\,\frac{2}{5};\,\frac{3}{7};\,\frac{4}{15};\,\frac{5}{31}\)

\(1;\,\frac{2}{3};\,\frac{3}{8};\,\frac{4}{15};\,\frac{5}{31}\)

\(1;\,\frac{2}{3};\,\frac{3}{7};\,\frac{4}{15};\,\frac{5}{31}\)

\(-4\)

\(18\)

\(-29\)

\(-25\)

\(q=-4\)

\(q=-6\)

\(q=6\)

\(q=4\)

\(\frac{\pi }{3}\)

\(\frac{7\pi }{12}\)

\(\frac{\pi }{6}\)

\(\frac{\pi }{4}\)