Giải thích các bước giải:
Từ `x``+``y``−``2``=``0``→``x``+``y``=``2`
`→``x`` =``2``−``y`
`A``=``x^3``−``2x^2``−``xy^2``+``2xy``+``2y``+``2x``−``2`
`A``=``x^3``−``2x^2``+`(`2xy``−``xy^2`)`+`(`2x``+``2y`)`+``2`
`A``=``x^3``−``2x^2``+`(`xy`.(`2−y`))`+`(`2`.(`x+y`))`+``2`
`A``=``x^3``−``2x^2``+``x2y``+``2.2``+``2`
`A``=``x^3``−``x^2`(`2−y`)`+``4``+``2`
`A``=``x^3`` −``x^3``+``6`
`A``=``6`