A.\(\dfrac{{2a}}{3}\)  
B.\(a\sqrt 3 \)   
C.\(\dfrac{{3a}}{4}\)  
D.\(\dfrac{{a\sqrt 3 }}{2}\)

A.\(\left[ \begin{array}{l}m = 1\\m =  - 2\end{array} \right.\)  
B.\(\left[ \begin{array}{l}m = 1\\m = 2\end{array} \right.\)   
C.\(\left[ \begin{array}{l}m =  - 1\\m = 2\end{array} \right.\)  
D.\(\left[ \begin{array}{l}m =  - 1\\m =  - 2\end{array} \right.\)

A.\(4\)
B.\(3\)
C.\(2\)
D.\(1\)

A.\(2\)  
B.\(8\)   
C.\(4\)  
D.\(6\)

A.\(1\)  
B.\( - 1\)   
C.\(\dfrac{1}{2}\)  
D.\( - \dfrac{1}{2}\)

A.\(\dfrac{x}{2} + \dfrac{y}{3} + \dfrac{z}{2} = 1\)  
B.\(\dfrac{x}{2} + \dfrac{y}{{ - 3}} + \dfrac{z}{2} = 1\)   
C.\(\dfrac{x}{{ - 3}} + \dfrac{y}{2} + \dfrac{z}{2} = 1\)  
D.\(\dfrac{x}{2} + \dfrac{y}{{ - 2}} + \dfrac{z}{3} = 1\)

A.\(y = {x^3} - 3x\)  
B.\(y = \dfrac{{3x + 1}}{{2x - 1}}\)  
C.\(y = {x^3} - 3x + 1\)  
D.\(y = {x^4} + 2x\)

A.\(D = \left( {0; + \infty } \right)\)
B.\(D = \left( { - 1; + \infty } \right)\backslash \left\{ 0 \right\}\)
C.\(D = \left( { - \infty ; + \infty } \right)\)
D.\(D = \left( { - 1; + \infty } \right)\)

A.\(\sqrt {13} \)  
B.\(13\)  
C.\(5\)  
D.\(\sqrt 5 \)

A.\(\left( {1;2} \right)\)
B.\(\left( {1;2} \right]\)
C.\(\left( { - \infty ;2} \right]\)
D.\(\left[ {2; + \infty } \right)\)