`( x - 2021 )^2021 = ( x - 2021^2022 )`
`⇔ ( x - 2021 )^2022 - ( x - 2021 )^2021 = 0`
`⇔ ( x - 2021 )^2021 . ( x - 2021 ) - ( x - 2021 )^2021 = 0`
`⇔ ( x - 2021 )^2021 . ( x - 2021 - 1 ) = 0`
`⇔` \(\left[ \begin{array}{l}( x - 2021 )^{2021} = 0\\x - 2021 - 1 = 0\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x - 2021 = 0\\x - 2022 = 0\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x = 2021\\x = 2022\end{array} \right.\)
Vậy `; x ∈ { 2021 ; 2022 } .`
