JEE Main & Advanced
Sample Paper
JEE Main - Mock Test - 34
question_answer
If \[{{D}_{k}}\left| \begin{matrix} 1 & n & n \\ 2k & {{n}^{2}}+n+1 & {{n}^{2}}+n \\ 2k-1 & {{n}^{2}} & {{n}^{2}}+n+1 \\ \end{matrix} \right|\] and \[\sum\limits_{k=1}^{n}{{{D}_{k}}=56}\] then find value of n.