Practicing Success
Statement-1: If A is a non-singular square matrix of order n, then $|adj\, A|=|A|^{n-1}$ Statement-2: For any square matrix A of order n, $A (adj\, A) =|A| I$ and $|kA|=k|A|$ |
Statement-1 is True, Statement-2 is true; Statement-2 is a correct explanation for Statement-1. Statement-1 is True, Statement-2 is True; Statement-2 is not a correct explanation for Statement-1. Statement-1 is True, Statement-2 is False. Statement-1 is False, Statement-2 is True. |
Statement-1 is True, Statement-2 is False. |
We know that $A(adj\, A) =|A| I$ $∴|A (adj\, A)| = ||A|I|=| A|^n |A|$ $[∵ |kA|=k^n |A|]$ $⇒|A||adj\, A|=|A|^n$ $⇒|adj\, A|=|A|^{n-1}$ So, statement-1 is true. But, statement-2 is false. Because, $|kA|=k^n |A|$. |