Region shading with multiple inequalities

Shade a region on an Argand diagram defined by two or more simultaneous inequalities involving modulus and/or argument conditions.

85 questions · Standard +0.3

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AQA Further Paper 1 2022 June Q8
11 marks Standard +0.8
  1. The complex number \(w\) is such that $$\arg(w + 2i) = \tan^{-1}\frac{1}{2}$$ It is given that \(w = x + iy\), where \(x\) and \(y\) are real and \(x > 0\) Find an equation for \(y\) in terms of \(x\) [2 marks]
  2. The complex number \(z\) satisfies both $$-\frac{\pi}{2} \leq \arg(z + 2i) \leq \tan^{-1}\frac{1}{2} \quad \text{and} \quad |z - 2 + 3i| \leq 2$$ The region \(R\) is the locus of \(z\) Sketch the region \(R\) on the Argand diagram below. [4 marks] \includegraphics{figure_1}
  3. \(z_1\) is the point in \(R\) at which \(|z|\) is minimum.
    1. Calculate the exact value of \(|z_1|\) [3 marks]
    2. Express \(z_1\) in the form \(a + ib\), where \(a\) and \(b\) are real. [2 marks]
AQA Further Paper 2 2023 June Q10
8 marks Challenging +1.2
The region \(R\) on an Argand diagram satisfies both \(|z + 2\text{i}| \leq 3\) and \(-\frac{\pi}{6} \leq \arg(z) \leq \frac{\pi}{2}\)
  1. Sketch \(R\) on the Argand diagram below. [3 marks] \includegraphics{figure_10a}
  2. Find the maximum value of \(|z|\) in the region \(R\), giving your answer in exact form. [5 marks]
OCR Further Pure Core 1 2021 November Q1
6 marks Moderate -0.8
  1. Sketch on a single Argand diagram the loci given by
    1. \(|z - 1 + 2\mathrm{i}| = 3\), [2]
    2. \(|z + 1| = |z - 2|\). [2]
  2. Indicate, by shading, the region of the Argand diagram for which \(|z - 1 + 2\mathrm{i}| \leqslant 3\) and \(|z + 1| \leqslant |z - 2|\). [2]
OCR MEI Further Pure Core AS 2018 June Q9
9 marks Standard +0.3
Fig. 9 shows a sketch of the region OPQ of the Argand diagram defined by $$\left\{z : |z| \leq 4\sqrt{2}\right\} \cap \left\{z : -\frac{1}{4}\pi \leq \arg z \leq \frac{1}{4}\pi\right\}.$$ \includegraphics{figure_9}
  1. Find, in modulus-argument form, the complex number represented by the point P. [2]
  2. Find, in the form \(a + ib\), where \(a\) and \(b\) are exact real numbers, the complex number represented by the point Q. [3]
  3. In this question you must show detailed reasoning. Determine whether the points representing the complex numbers
    lie within this region. [4]
SPS SPS FM 2020 September Q12
9 marks Standard +0.3
Fig. 9 shows a sketch of the region OPQ of the Argand diagram defined by $$\{z : |z| \leq 4\sqrt{2}\} \cap \left\{z : \frac{1}{4}\pi \leq \arg z \leq \frac{3}{4}\pi\right\}.$$ \includegraphics{figure_9}
  1. Find, in modulus-argument form, the complex number represented by the point P. [2]
  2. Find, in the form \(a + ib\), where \(a\) and \(b\) are exact real numbers, the complex number represented by the point Q. [3]
  3. In this question you must show detailed reasoning. Determine whether the points representing the complex numbers
    lie within this region. [4]
SPS SPS FM Pure 2023 June Q8
7 marks Challenging +1.2
  1. Shade on an Argand diagram the set of points $$\left\{z \in \mathbb{C} : |z - 4i| \leqslant 3\right\} \cap \left\{z \in \mathbb{C} : -\frac{\pi}{2} < \arg(z + 3 - 4i) \leqslant \frac{\pi}{4}\right\}$$ [5]
The complex number \(w\) satisfies \(|w - 4i| = 3\).
  1. Find the maximum value of \(\arg w\) in the interval \((-\pi, \pi]\). Give your answer in radians correct to 2 decimal places. [2]
SPS SPS FM Pure 2025 January Q6
12 marks Standard +0.3
You are given the complex number \(w = 2 + 2\sqrt{3}i\).
  1. Express \(w\) in modulus-argument form. [3]
  2. Indicate on an Argand diagram the set of points, \(z\), which satisfy both of the following inequalities. $$-\frac{\pi}{2} \leq \arg z \leq \frac{\pi}{3} \text{ and } |z| \leq 4$$ Mark \(w\) on your Argand diagram and find the greatest value of \(|z - w|\). [9]
OCR FP1 AS 2017 December Q2
9 marks Standard +0.3
The loci \(C_1\) and \(C_2\) are given by \(|z - (3 + 2i)| = 2\) and \(\arg(z - (3 + 2i)) = \frac{5\pi}{6}\) respectively.
  1. Sketch \(C_1\) and \(C_2\) on a single Argand diagram. [4]
  2. Find, in surd form, the number represented by the point of intersection of \(C_1\) and \(C_2\). [3]
  3. Indicate, by shading, the region of the Argand diagram for which $$|z - (3 + 2i)| \leq 2 \text{ and } \frac{5\pi}{6} \leq \arg(z - (3 + 2i)) \leq \pi.$$ [2]
OCR FP1 AS 2017 Specimen Q4
4 marks Moderate -0.3
Draw the region of the Argand diagram for which \(|z - 3 - 4i| \leq 5\) and \(|z| \leq |z - 2|\). [4]
Pre-U Pre-U 9795 Specimen Q1
4 marks Standard +0.3
The region \(R\) of an Argand diagram is defined by the inequalities $$0 \leqslant \arg(z + 4\mathrm{i}) \leqslant \frac{1}{4}\pi \quad \text{and} \quad |z| \leqslant 4.$$ Draw a clearly labelled diagram to illustrate \(R\). [4]