engineering recuitment GATE ME 2023-24 Test Series Engineering Mathematics Linear Algebra Matrix Algebra
Let \(A = \left( {\begin{array}{*{20}{c}} 1&2\\ 3&4 \end{array}} \right)\)and \(B = \left( {\begin{array}{*{20}{c}} a&0\\ 0&b \end{array}} \right)\), a, b ∈ N. Then,
1
There cannot exist any B such that AB = BA
2
There exists more than one but finite number of B's such that AB = BA
3
There exists exactly one B such that AB = BA
4
There exists infinitely many B's such that AB = BA