Mathematics - Matrices Question with Solution | TestHub

If $\det A=\pm 1$, then $A^{-1}$ exists but all its entries are not necessarily integers

If $\det A\ne \pm 1$, then $A^{-1}$ exists and all its entries are non-integers

If $\det A=\pm 1$, then $A^{-1}$ exists and all its entries are integers

If $\det A=\pm 1$, then $A^{-1}$ need not exist