Question

If A is a 3 × 3 matrix, |A| ≠ 0 and |3A| = k |A|, then write the value of k.

Answer 1

Here, |3A| = k|A| 

⇒3³ |A| = k|A| [∵ |kA| = kn|A| where n is order of A] 

⇒ 27 |A| = k|A| 

⇒ k = 27