Edexcel FP1 2017 June — Question 4

Exam BoardEdexcel
ModuleFP1 (Further Pure Mathematics 1)
Year2017
SessionJune
TopicComplex Numbers Arithmetic
TypeComplex number parameter problems

4. (i) The complex number \(w\) is given by $$w = \frac { p - 4 \mathrm { i } } { 2 - 3 \mathrm { i } }$$ where \(p\) is a real constant.
  1. Express \(w\) in the form \(a + b i\), where \(a\) and \(b\) are real constants. Give your answer in its simplest form in terms of \(p\). Given that \(\arg w = \frac { \pi } { 4 }\)
  2. find the value of \(p\).
    (ii) The complex number \(z\) is given by $$z = ( 1 - \lambda i ) ( 4 + 3 i )$$ where \(\lambda\) is a real constant. Given that $$| z | = 45$$ find the possible values of \(\lambda\).
    Give your answers as exact values in their simplest form.
    II