Đáp án:
Bạn tham khảo nhé!!!
Giải thích các bước giải:
\(\begin{array}{l}
A = {2018^{12}} + {2018^{11}} + .... + {2018^2} + 2018\\
= \left( {{{2018}^{12}} + {{2018}^{11}} + {{2018}^{10}}} \right) + \left( {{{2018}^9} + {{2018}^8} + {{2018}^7}} \right) + \left( {{{2018}^6} + {{2018}^5} + {{2018}^4}} \right) + \left( {{{2018}^3} + {{2018}^2} + 2018} \right)\\
= {2018^{10}}\left( {{{2018}^2} + 2018 + 1} \right) + {2018^7}\left( {{{2018}^2} + 2018 + 1} \right) + {2018^4}\left( {{{2018}^2} + 2018 + 1} \right) + 2018\left( {{{2018}^2} + 2018 + 1} \right)\\
= \left( {{{2018}^2} + 2018 + 1} \right)\left( {{{2018}^{10}} + {{2018}^7} + {{2018}^4} + 2018} \right)\\
\Rightarrow A\,\, \vdots \,\,\left( {{{2018}^{10}} + {{2018}^7} + {{2018}^4} + 2018} \right).
\end{array}\)
