A.\(D = \mathbb{R}\)
B.\(D = \left( {2; + \infty } \right)\)
C.\(D = \mathbb{R}\backslash \left\{ 2 \right\}\)
D.\(D = \left[ {2; + \infty } \right)\)

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

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

A.\({\log _a}b - {\log _a}c = {\log _a}\frac{b}{c}\) 
B.\({\log _a}b - {\log _a}c = {\log _a}\left( {bc} \right)\)
C.\({\log _a}b - {\log _a}c = {\log _a}\left| {b - c} \right|\)
D.\({\log _a}b - {\log _a}c = {\log _a}\left( {b - c} \right)\)

A.\(\int {\left[ {f\left( x \right) + g\left( x \right)} \right]dx}  = \int {f\left( x \right)dx}  + \int {g\left( x \right)dx} \)
B.\(\int {\frac{{f\left( x \right)}}{{g\left( x \right)}}dx}  = \frac{{\int {f\left( x \right)dx} }}{{\int {g\left( x \right)dx} }}\)
C.\(\int {\left[ {f\left( x \right) - g\left( x \right)} \right]dx}  = \int {f\left( x \right)dx}  - \int {g\left( x \right)dx} \)
D.\(\int {kf\left( x \right)dx}  = k\int {f\left( x \right)dx} \) (\(k\) là hàng số khác 0)

A.\({u_3} = 18\)
B.\({u_3} = 10\)
C.\({u_3} = 12\)
D.\({u_3} = 7\)

A.\(1\)
B.\(2\)
C.\(3\)
D.\(0\)

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

A.\(x - y + 2z + 2 = 0\)
B.\(x - y - 2z - 6 = 0\)
C.\(x - y + 2z - 2 = 0\)
D.\( - x + y + 2z - 2 = 0\)

A.\(\left| z \right| = \sqrt {13} \)
B.\(\left| z \right| = 5\)
C.\(\left| z \right| = 13\)
D.\(\left| z \right| = \sqrt 5 \)