A.\(\left\{ { \pm 2i;\,\,\dfrac{1}{2} \pm \dfrac{{\sqrt 3 }}{2}i} \right\}\)
B.\(\left\{ {2i} \right\}\)
C.\(\left\{ { - 2i;\,\, - \dfrac{1}{2} - \dfrac{{\sqrt 3 }}{2}i} \right\}\)
D.\(\left\{ { - 2i;\,\,\dfrac{1}{2} - \dfrac{{\sqrt 3 }}{2}i} \right\}\)

A.\(y = f\left( x \right) =  - {x^3} + 3x + 1\)
B.\(y = f\left( x \right) =  - {x^3} + 3x - 1\)
C.\(y = f\left( x \right) = {x^3} - 3x - 1\)
D.\(y = f\left( x \right) = {x^3} - 3x + 1\)

A.\(\dfrac{{a\sqrt 2 }}{2}\)
B.\(2a\)
C.\(\dfrac{{a\sqrt {15} }}{5}\)
D.\(\dfrac{{a\sqrt 7 }}{7}\)

A.Tam giác \(ABD\) là tam giác đều.
B.Bốn điểm \(A,\,\,B,\,\,C,\,\,D\) tạo thành tứ diện.
C.\(AB\) vuông góc với \(CD\).
D.Tam giác \(BCD\) là tam giác vuông.

A.the figurative meanings of the word culture
B.the distinction between culture and civilization
C.the derivatives of the word culture
D.the multiplicity of meanings of the word culture

A.the figurative meanings of the word culture
B.the distinction between culture and civilization
C.the derivatives of the word culture
D.the multiplicity of meanings of the word culture

A.qualities
B.skills
C.aspects
D.fields

A.comes from a source that has not been identified
B.develops from Greek and Roman literature and history
C.is related to the preparation and use of land for farming
D.derives from the same root as civilization does

A.regular
B.dense
C.balanced
D.unchanged

A.Cultures
B.Developments
C.Evolutions
D.Conceptions