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If Dk=|(1, n, n),(2k, n^2+n+1,n^2+n),(2k...

If `D_k=|(1, n, n),(2k, n^2+n+1,n^2+n),(2k-1,n^2,n^2+n+1)| and sum_(k=1)^n D_k=56.` then `n` equals `4` b. `6` c. `8` d. none of these

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RD SHARMA ENGLISH-DETERMINANTS-All Questions
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