n/fi1/fi)n/2+nfi=D => physically then n^2/fi^2+nfi is 2n/2fi+nfi is n/fi+nfi is n(fi+1)/fi , ah I dont know, it is exam from 2005 ;D but I can remember D computation :) of it is 21:00 fast and furious into the bed ;) how could i get again 2.618/1.618=again 1.618 for n=1 lets compute 1/fi+1=(1+fi)/fi which is same equation :) proved! ah what was the joke? [fi] 1x1 matrix must be again fi, which is again fi but written as 1+1.618)/1.618=1.618 Thank you the army Dr Ondis and Dr Chovanec, my exam in 2005 was for A.

https://en.wikipedia.org/wiki/Determinant

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