2.
$$z _ { 1 } = - 2 + \mathrm { i }$$
- Find the modulus of \(z _ { 1 }\).
- Find, in radians, the argument of \(z _ { 1 }\), giving your answer to 2 decimal places.
The solutions to the quadratic equation
$$z ^ { 2 } - 10 z + 28 = 0$$
are \(z _ { 2 }\) and \(z _ { 3 }\).
- Find \(z _ { 2 }\) and \(z _ { 3 }\), giving your answers in the form \(p \pm i \sqrt { } q\), where \(p\) and \(q\) are integers.
- Show, on an Argand diagram, the points representing your complex numbers \(z _ { 1 } , z _ { 2 }\) and \(z _ { 3 }\).