Đáp án + giải thích bước giải :
Điều kiện `x,y ∈ Z`
`(x + 1) (y - 2) = 10`
`-> x + 1, y - 2 ∈ Ư (10) = {±1; ±2; ±5; ±10}`
`-> x + 1 ∈ Ư (10) = {±1; ±2; ±5; ±10} (x ∈ Z)`
`->x + 1 = 1 ->x = 0`
`->x + 1 = -1 ->x= -2`
`->x + 1 = 2 -> x = 1`
`-> x + 1 = -2 -> x = -3`
`-> x + 1 = 5 -> x = 4`
`-> x + 1 = -5 -> x = -6`
`-> x + 1 = 10 -> x = 9`
`-> x + 1 = -10 -> x = -11`
`-> y - 2 ∈ Ư (10) = {±1; ±2; ±5; ±10} (y ∈ Z)`
`-> y - 2 = 1 -> x = 3`
`-> y - 2 = -1 -> y = 1`
`-> y - 2 = 2 -> y = 4`
`-> y - 2 = -2 -> y = 0`
`-> y - 2 = 5 -> y = 7`
`-> y - 2 = -5 -> y = -3`
`-> y - 2 = 10 -> y = 12`
`-> y - 2 = -10 -> y = -8`
Vậy ..
