SPS SPS FM Pure 2022 June — Question 6 7 marks

Exam BoardSPS
ModuleSPS FM Pure (SPS FM Pure)
Year2022
SessionJune
Marks7
TopicComplex Numbers Argand & Loci
TypeArgument calculations and identities
DifficultyModerate -0.3 This is a straightforward Further Maths complex numbers question testing standard techniques: modulus/argument calculation (routine), algebraic manipulation with complex numbers (multiply out and divide), and using argument conditions (simple angle geometry). All parts are textbook exercises requiring no problem-solving insight, though the multi-part structure and FM context place it slightly below average difficulty overall.
Spec4.02a Complex numbers: real/imaginary parts, modulus, argument4.02e Arithmetic of complex numbers: add, subtract, multiply, divide

The complex number \(w\) is given by $$w = 10 - 5i$$
  1. Find \(|w|\). [1]
  2. Find \(\arg w\), giving your answer in radians to 2 decimal places. [1]
The complex numbers \(z\) and \(w\) satisfy the equation $$(2 + i)(z + 3i) = w$$
  1. Use algebra to find \(z\), giving your answer in the form \(a + bi\), where \(a\) and \(b\) are real numbers. [4]
Given that $$\arg(\lambda + 9i + w) = \frac{\pi}{4}$$ where \(\lambda\) is a real constant,
  1. find the value of \(\lambda\). [1]

The complex number $w$ is given by
$$w = 10 - 5i$$

\begin{enumerate}[label=(\alph*)]
\item Find $|w|$. [1]

\item Find $\arg w$, giving your answer in radians to 2 decimal places. [1]
\end{enumerate}

The complex numbers $z$ and $w$ satisfy the equation
$$(2 + i)(z + 3i) = w$$

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item Use algebra to find $z$, giving your answer in the form $a + bi$, where $a$ and $b$ are real numbers. [4]
\end{enumerate}

Given that
$$\arg(\lambda + 9i + w) = \frac{\pi}{4}$$

where $\lambda$ is a real constant,

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{3}
\item find the value of $\lambda$. [1]
\end{enumerate}

\hfill \mbox{\textit{SPS SPS FM Pure 2022 Q6 [7]}}