Same chapter3 marksDifficulty: Medium
If A = [[1, 2], [3, 4]], find its transpose and state its order.
Matrices
2 marksDifficulty: Medium
Give an example to show that matrix multiplication is not commutative.
Original Khojo Papers practice question — not from a past board paper.
Answer
Take A = [[1, 0], [0, 0]] and B = [[0, 1], [0, 0]]. Then AB = [[0, 1], [0, 0]] but BA = [[0, 0], [0, 0]], so AB ≠ BA.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Even when both products are defined and have the same order, they need not be equal.
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Find the product [[1, 2], [3, 4]] × [[2, 0], [1, 3]].
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Same chapter1 markDifficulty: Medium
If A is of order 3 × 2 and B is of order 2 × 3, then BA is of order:
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