AQA FP2 2011 January — Question 1 5 marks

Exam BoardAQA
ModuleFP2 (Further Pure Mathematics 2)
Year2011
SessionJanuary
Marks5
PaperDownload PDF ↗
TopicComplex Numbers Argand & Loci
TypeOptimization of modulus on loci
DifficultyStandard +0.3 This is a straightforward Further Maths question requiring recognition that |z - (4-3i)| = 5 is a circle, sketching it, finding the intersection with the positive real axis (arg z = 0), and calculating a modulus. All steps are routine applications of standard locus definitions with no novel problem-solving required.
Spec4.02k Argand diagrams: geometric interpretation4.02o Loci in Argand diagram: circles, half-lines

1
  1. Sketch on an Argand diagram the locus of points satisfying the equation $$| z - 4 + 3 \mathrm { i } | = 5$$
    1. Indicate on your diagram the point \(P\) representing \(z _ { 1 }\), where both $$\left| z _ { 1 } - 4 + 3 \mathrm { i } \right| = 5 \quad \text { and } \quad \arg z _ { 1 } = 0$$
    2. Find the value of \(\left| z _ { 1 } \right|\).

1
\begin{enumerate}[label=(\alph*)]
\item Sketch on an Argand diagram the locus of points satisfying the equation

$$| z - 4 + 3 \mathrm { i } | = 5$$
\item \begin{enumerate}[label=(\roman*)]
\item Indicate on your diagram the point $P$ representing $z _ { 1 }$, where both

$$\left| z _ { 1 } - 4 + 3 \mathrm { i } \right| = 5 \quad \text { and } \quad \arg z _ { 1 } = 0$$
\item Find the value of $\left| z _ { 1 } \right|$.
\end{enumerate}\end{enumerate}

\hfill \mbox{\textit{AQA FP2 2011 Q1 [5]}}