A.\(\left( {3x + 1} \right)\left( {x - 2} \right)\)
B.\(\left( {3x - 1} \right)\left( {x - 2} \right)\)
C.\(\left( {3x + 1} \right)\left( {x + 2} \right)\)
D.\(\left( {3x - 1} \right)\left( {x + 2} \right)\)

A.màu tím và tần số f.
B.màu cam và tần số 1,5f.
C.màu cam và tần số f.
D.màu tím và tần số 1,5f.

A.\({x^3} + \dfrac{1}{2}{x^2} - \dfrac{1}{2}x + \dfrac{1}{8} = 0\)
B.\({x^3} + \dfrac{1}{2}{x^2} + \dfrac{1}{2}x + \dfrac{1}{8} = 0\)
C. \({x^3} - \dfrac{1}{2}{x^2} - \dfrac{1}{2}x + \dfrac{1}{8} = 0\)
D.\({x^3} - \dfrac{1}{2}{x^2} - \dfrac{1}{2}x - \dfrac{1}{8} = 0\)

A.\(\left( {x - y - 2xy} \right)\left( {x - y + 2xy} \right)\)
B.\(\left( {x - y - 2xy} \right)\left( {x + y + 2xy} \right)\)
C.\(\left( {x + y - 2xy} \right)\left( {x - y + 2xy} \right)\)
D.\(\left( {x + y - 2xy} \right)\left( {x + y + 2xy} \right)\)

A.\(\left( {x - y - 2xy} \right)\left( {x - y + 2xy} \right)\)
B.\(\left( {x - y - 2xy} \right)\left( {x + y + 2xy} \right)\)
C.\(\left( {x + y - 2xy} \right)\left( {x - y + 2xy} \right)\)
D.\(\left( {x + y - 2xy} \right)\left( {x + y + 2xy} \right)\)

A.\(\left( {2x - 3y} \right)\left( {2x + 3y} \right)\left( {x + y} \right)\)
B.\(\left( {2x - 3y} \right)\left( {x + y} \right)\left( {x - y} \right)\)
C.\(\left( {2x + 3y} \right)\left( {x + y} \right)\left( {x - y} \right)\)
D.\(\left( {2x - 3y} \right)\left( {2x + 3y} \right)\left( {x - y} \right)\)

A.\(2y\left( {3{x^2} + {y^2}} \right)\)
B.\(2x\left( {3{x^2} + {y^2}} \right)\)
C.\(2x\left( {{x^2} + 3{y^2}} \right)\)
D.\(2y\left( {{x^2} + 3{y^2}} \right)\)

A.\(x \in \left\{ {0;\,\,3} \right\}\)
B.\(x \in \left\{ {0;\,\, - 3} \right\}\)
C.\(x \in \left\{ {0;\,\,\dfrac{1}{3}} \right\}\)
D.\(x \in \left\{ {0;\,\,1} \right\}\)

A.\(x \in \left\{ {0;\,\,3} \right\}\)
B.\(x \in \left\{ {0;\,\, - 3} \right\}\)
C.\(x \in \left\{ {0;\,\,\dfrac{1}{3}} \right\}\)
D.\(x \in \left\{ {0;\,\,1} \right\}\)

A.\(x \in \left\{ { - 3;\,\,3} \right\}\)
B.\(x \in \left\{ { - 9;\,\,0;\,\,9} \right\}\)
C.\(x \in \left\{ {0;\,\,9} \right\}\)
D.\(x \in \left\{ { - 3;\,\,0;\,\,3} \right\}\)