9 The position vectors of the points \(A , B\) and \(C\) are
$$\begin{aligned}
& \mathbf { a } = 2 \mathbf { i } + \mathbf { j } + 2 \mathbf { k }
& \mathbf { b } = - \mathbf { i } - 8 \mathbf { j } + 2 \mathbf { k }
& \mathbf { c } = - 2 \mathbf { j }
\end{aligned}$$
respectively.
9
- Find the area of the triangle \(A B C\)
9 - The points \(A , B\) and \(C\) all lie in the plane \(\Pi\)
Find an equation of the plane \(\Pi\), in the form \(\mathbf { r } \cdot \mathbf { n } = d\)
\(\mathbf { 9 ( c ) } \quad\) The point \(P\) has position vector \(\mathbf { p } = \mathbf { i } + 4 \mathbf { j } + 2 \mathbf { k }\)
Find the exact distance of \(P\) from \(\Pi\)