6 The matrices \(\mathbf { A }\) and \(\mathbf { B }\) are given by \(\mathbf { A } = \left( \begin{array} { r r } t & 6
t & - 2 \end{array} \right)\) and \(\mathbf { B } = \left( \begin{array} { r r } 2 t & 4
t & - 2 \end{array} \right)\) where \(t\) is a constant.

1. Show that \(| \mathbf { A } | = | \mathbf { B } |\).
2. Verify that \(| \mathbf { A B } | = | \mathbf { A } \| \mathbf { B } |\).
3. Given that \(| \mathbf { A B } | = - 1\) explain what this means about the constant \(t\).