If A and B are square matrices of order 3 x 3 such that A is an orthogonal matrix and B is a skew-symmetric matrix, then which of the following statements is true?

$|AB|=1$ $|AB|=0$ $|AB|=-1$ none of these

$|AB|=0$

We have, A an orthogonal matrix $⇒ |A|=±1$ B a skew-symmetric matrix of odd order $⇒ |B|=0$ $∴|AB|=|A||B|⇒|AB|=(±1)× 0=0$.