Cho $\left( {19xy - 7{x^3}y + 9{x^2}} \right) - A = 10xy - 2{x^3}y - 9{x^2}.$ Đa thức $A$ là:

$7{x^2} + 6{y^2}$

$5{x^2} + 5{y^2}$    

$6{x^2} + 6{y^2}$

$6{x^2} - 6{y^2}$

$- {x^2}y - 7x{y^2} + 26$

$- 5{x^2}y + 3x{y^2} + 6$

$- 5{x^2}y - 3x{y^2} + 6$

$5{x^2}y - 3x{y^2} - 6$

$2$

$3$

$4$

$6$

$- {y^2} - 2{x^3}y$

${y^2} + 2{x^3}y$

${y^2} - 2{x^3}y$

$- {y^2} + 2{x^3}y$

$- 4{x^2}{y^3} + 3xy + 5{x^2}{y^2}$

$3xy - 7{x^2}{y^2}$

$- 4{x^2}{y^3} + 3xy - 7{x^2}{y^2}$

$3xy + 7{x^2}{y^2}$

$4{x^2}{y^3} - 7xy - {x^2}{y^2}$

$4{x^2}{y^3} + 7xy + {x^2}{y^2}$  

$3xy + 5{x^2}{y^2}$

$4{x^2}{y^3} - 7xy + {x^2}{y^2}$

$- 2{x^2}{y^3} + 3xy - 11{x^2}{y^2}$

$- 2{x^2}{y^3} - 3xy - 11{x^2}{y^2}$

$- 2{x^2}{y^3} + 3xy + 11{x^2}{y^2}$

$2{x^2}{y^3} + 3xy + 11{x^2}{y^2}$