Q. 54.5( 11 Votes )

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

Answer :

Given: |3A| = k|A|

Now, we know that |xA| = x^{n}|A|, where n is the order of square matrix.

Therefore,

|3A| = 3^{3}|A|

|3A| = 27|A|

Hence, k = 27.

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