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A \(D = R\backslash \left\{ 1 \right\}\)

B \(D = R\backslash \left\{ 0 \right\}\)

C \(D = R\)

D \(D = \left( {0; + \infty } \right)\)

A \(R\)

B \(\left( {1; + \infty } \right)\)

C \(R\backslash \left\{ 1 \right\}\)

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

A \(\left( { - \infty ; - \frac{1}{2}} \right)\)

B \(\left( { - \infty ;\frac{1}{2}} \right)\)

C \(\left( {\frac{1}{2}; + \infty } \right)\)

D \(\left( { - \frac{1}{2}; + \infty } \right)\)

A \(\left( { - \infty ;2} \right)\)

B \(\left( { - 1;2} \right)\backslash \left\{ 0 \right\}\)

C \(\left( { - 1;2} \right)\)

D \(\left( { - \infty ;2} \right)\backslash \left\{ 0 \right\}\)

A \(D = \left( {6; + \infty } \right)\)

B \(D = \left( {0; + \infty } \right)\)

C \(D = \left( { - \infty ;6} \right)\)

D R

A \(D = \left( {0; + \infty } \right)\)

B \(D = \left[ { - 2;2} \right]\)

C \(D = \left( { - 2;2} \right)\)

D \(D = \left[ {2; + \infty } \right)\)

A \(D = \left( { - \infty ;0} \right) \cup \left( {0; + \infty } \right)\)

B \(D = R\)

C \(D = \left( { - \infty ;1} \right) \cup \left( {3; + \infty } \right)\)

D \(D = \left( {0; + \infty } \right)\)

A \(x \ne 2\)

B \(x <  - 3\) hoặc \(x > 2\)

C \( - 3 \le x < 2\)

D \( - 3 < x < 2\)

A \(\left( { - 8; - 4} \right) \cup \left( {3; + \infty } \right)\)

B \(\left( { - \infty ; - 4} \right) \cup \left( {3; + \infty } \right)\)

C \(\left( { - 8;3} \right)\backslash \left\{ { - 4} \right\}\)

D \(\left( { - \infty ; - 2} \right] \cup \left[ { - 1; + \infty } \right)\)

A \(D = R\)

B \(D = \left( { - \infty ;0} \right)\)

C \(D = \left( { - \infty ;0} \right) \cup \left( {0; + \infty } \right)\)

D \(D = \left( {0; + \infty } \right)\)

A \(D = R\backslash \left\{ 2 \right\}\)

B \(D = \left( {2; + \infty } \right)\)

C \(D = \left( { - \infty ;2} \right)\)

D \(D = \left( { - 2; + \infty } \right) \cup \left( { - \infty ;2} \right)\)

A \(D = \left( {0; + \infty } \right)\)

B \(D = R\backslash \left\{ {16} \right\}\)

C \(D = \left( {0;16} \right)\)

D \(D = \left( {0;16} \right) \cup \left( {16; + \infty } \right)\)

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

B \(R\backslash \left\{ {\frac{\pi }{3} + k\pi ,\,\,k \in Z} \right\}\)

C \(R\backslash \left\{ {\pi  + k2\pi ;\,\,k \in Z} \right\}\)

D \(R\)

A \(D = \left( { - \infty ;0} \right] \cup \left( {1;2} \right] \cup \left[ {4; + \infty } \right)\)

B \(D = \left( { - \infty ;1} \right] \cup \left[ {4; + \infty } \right)\)

C \(D = \left( { - \infty ;1} \right) \cup \left( {4; + \infty } \right)\)

D \(D = \left( { - \infty ;0} \right] \cup \left[ {1;2} \right] \cup \left[ {4; + \infty } \right)\)

A \(m = 2\)

B \(\left[ \begin{array}{l}m > 2\\m <  - 2\end{array} \right.\)

C \(m < 2\)

D \( - 2 < m < 2\)

A \(D = \left( {1;4} \right)\)

B \(D = \left( { - \infty ;1} \right) \cup \left( {4; + \infty } \right)\)

C \(D = \left( { - \infty ;1} \right] \cup \left[ {4; + \infty } \right)\)

D \(D = \left[ {1;4} \right]\)

A \(\left[ {0;\frac{9}{4}} \right)\backslash \left\{ {\frac{1}{4}} \right\}\)

B \(\left[ {0;\frac{9}{4}} \right]\backslash \left\{ {\frac{1}{4}} \right\}\)  

C \(\left( {0;\frac{9}{4}} \right)\backslash \left\{ {\frac{1}{4}} \right\}\)     

D \(\left( {0;\frac{9}{4}} \right)\)

A \(\left[ {\frac{2}{3}; + \infty } \right)\)

B \(\left( {\frac{2}{3}; + \infty } \right)\)

C \(\left( {\frac{1}{3}; + \infty } \right)\)

D \(\left[ {\frac{2}{3};10} \right]\)

A \(m > \frac{1}{4}\)

B \(m > 0\)

C \(m \ge \frac{1}{4}\)

D \(m < \frac{1}{4}\)