- The transformation \(T\) from the \(z\)-plane to the \(w\)-plane is given by
$$w = \frac { z } { z + 4 \mathrm { i } } \quad z \neq - 4 \mathrm { i }$$
The circle with equation \(| z | = 3\) is mapped by \(T\) onto the circle \(C\) Determine
- a Cartesian equation of \(C\)
- the centre and radius of \(C\)