chép cùng 1 trang mạng

x2+xy+2023x+2022y+2023=0

\(x^{2} + x y + x + 2022 x + 2022 y + 2022 + 1 = 0\)

\(x \left(\right. x + y + 1 \left.\right) + 2022 \left(\right. x + y + 1 \left.\right) = - 1\)

\(\left(\right. x + 2022 \left.\right) \left(\right. x + y + 1 \left.\right) = - 1\)

\(x + 2022 = 1\) hoặc \(x + y + 1 = - 1\)

\(x + 2022 = - 1\) hoặc \(x + y + 1 = 1\)

\(x = - 2021\) và \(y = 2019\) hoặc \(x = - 2023\) và \(y = 2023\)

Vậy \left{\right. x ; y \left.\right) \in \left{\right. \left\{right. - 2021 ; 2019 \left.\right) ; \left{\right. - 2023 ; 2023 \left.\right) \left.\right}.

999...999 x 999...999 + 1999...999

= 999...999 x ( 1000...000 - 1 ) + 1000...000 + 999...999

= 999...999 000...000 + 1000...000 + 999...999

= 1000...000 ( với 4016 chữ số 0)