SPS SPS FM 2021 November — Question 3 6 marks

Exam BoardSPS
ModuleSPS FM (SPS FM)
Year2021
SessionNovember
Marks6
TopicComplex Numbers Argand & Loci
TypeCircle of Apollonius locus
DifficultyStandard +0.3 This is a standard locus problem requiring algebraic manipulation to convert the given condition into circle form. Students substitute z = x + iy, expand |z - 6i|² = 4|z - 3|², and complete the square. While it involves several algebraic steps, the technique is routine and commonly practiced in Further Maths complex numbers topics, making it slightly easier than average.
Spec4.02k Argand diagrams: geometric interpretation4.02o Loci in Argand diagram: circles, half-lines

The point \(P\) represents a complex number \(z\) on an Argand diagram such that $$|z - 6i| = 2|z - 3|.$$ Show that, as \(z\) varies, the locus of \(P\) is a circle, stating the radius and the coordinates of the centre of this circle. [6 marks]

The point $P$ represents a complex number $z$ on an Argand diagram such that
$$|z - 6i| = 2|z - 3|.$$

Show that, as $z$ varies, the locus of $P$ is a circle, stating the radius and the coordinates of the centre of this circle.
[6 marks]

\hfill \mbox{\textit{SPS SPS FM 2021 Q3 [6]}}