\(\mathbf { M } = \left( \begin{array} { c c } a & 1 \\ 1 & 2 - a \end{array} \right)\), where \(a\) is a constant.
- Find det M in terms of \(a\).
(2)
A triangle \(T\) is transformed to \(T ^ { \prime }\) by the matrix M .
Given that the area of \(T ^ { \prime }\) is 0 , - find the value of \(a\).
(3)