Are there conditions for a Matrice to be invertible or not?
And why det(A)=0 when A is invertible? Can someone give me a proof? , thank you.
I think I found the answer, I am not sure though, so if Matrix A is invertible then rankA=n when n is the number of columns or unknowns. However if RankA<n then we have a row with just only 0 and according to the properties of Determinants if we have a row with only zeros then detA=0
Is this correct?