Same chapter3 marksDifficulty: Medium
If A = [[2, 1], [0, 3]] and I is the 2 × 2 identity matrix, find AI and IA and state what this shows.
Matrices
1 markDifficulty: Medium
For matrices, which of the following is always true?
- aAB = BA
- bA + B = B + A when both have the same order
- cAB = 0 implies A = 0 or B = 0
- devery matrix has an inverse
Original Khojo Papers practice question — not from a past board paper.
Answer
A + B = B + A when both have the same order
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Matrix addition is commutative, but multiplication is not, a product can be zero without either factor being zero, and only certain square matrices have inverses.
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