Question

qn below

Answer 1

well we should first define a non-singular matrix ie
\[\det A \ne0\]

Answer 2

then?

Answer 3

\[\huge a_{11}a_{22}=a_{12}a_{21}\]

Answer 4

since
\[\det A=a_{11}a_{22}-a_{12}a_{21}\ne 0\]
ie it shud have an inverse
i meant\[\huge a_{11}a_{22} \ne a_{12}a_{21}\]

Answer 5

but we are given\[\huge a_{11}= a_{22}\implies a_{11}a_{22} =b^2=a_{12}a_{21}\]
we have to find such pairs
where \[b \in {(0,1,2)}\]