Giá trị của biểu thức $D = {x^3}-{x^2}y-x{y^2} + {y^3}$ khi $x = y$ là

$\left( {x - 5} \right)\left( {x + 2} \right)$.

$\left( {x - 5} \right)\left( {x - 2} \right)$.

$\left( {x + 5} \right)\left( {x + 2} \right)$.

$\left( {x - 5} \right)\left( {2 - x} \right)$.

$\left( {m - 1} \right)\left( {n + 1} \right)\left( {{n^2} - n + 1} \right)$

${n^2}\left( {n + 1} \right)\left( {m - 1} \right)$

$\left( {m + 1} \right)\left( {{n^2} + 1} \right)$

$\left( {{n^3} + 1} \right)\left( {m - 1} \right)$

${\left( {{x^4} - 2} \right)^2} - {\left( {2{x^2}} \right)^2}$.

${\left( {{x^4} + 4} \right)^2} - {\left( {4{x^2}} \right)^2}$.

${\left( {{x^4} + 2} \right)^2} - {\left( {4{x^2}} \right)^2}$.

${\left( {{x^4} + 2} \right)^2} - {\left( {2{x^2}} \right)^2}$.

$2x + y + 1$

$2x - y + 1$

$2x - y$         

$2x + y$

${x^3} + {x^2} - 4x - 4 = \left( {x - 2} \right)\left( {x + 2} \right)\left( {x + 1} \right)$.

${x^2} + 10x + 24 = \left( {x + 4} \right)\left( {x + 6} \right)$.              

Cả A, B đều sai

Cả A, B đều đúng.

$16{x^3} - 54{y^3} = 2\left( {2x - 3y} \right)\left( {4{x^2} + 6xy + 9{y^2}} \right)$.

${x^2} - 9 + \left( {2x + 7} \right)\left( {3 - x} \right) = \left( {x - 3} \right)\left( { - x - 4} \right)$.

$\;{x^4} - 4{x^3} + 4{x^2} = {x^2}{\left( {x - 2} \right)^2}.$    

$\;4{x^3} - 4{x^2} - x + 1 = \left( {2x - 1} \right)\left( {2x + 1} \right)\left( {x + 1} \right).$

$\left( A \right)$ đúng, $\left( B \right)$ sai.

$\left( A \right)$ sai, $\left( B \right)$ đúng.

$\left( A \right)$, $\left( B \right)$ đều sai

$\left( A \right)$, $\left( B \right)$ đều đúng.