CAIE P3 2021 November — Question 3

Exam BoardCAIE
ModuleP3 (Pure Mathematics 3)
Year2021
SessionNovember
TopicComplex Numbers Arithmetic
TypeComplex conjugate properties and proofs

3
  1. Given the complex numbers \(u = a + \mathrm { i } b\) and \(w = c + \mathrm { i } d\), where \(a , b , c\) and \(d\) are real, prove that \(( u + w ) ^ { * } = u ^ { * } + w ^ { * }\).
  2. Solve the equation \(( z + 2 + \mathrm { i } ) ^ { * } + ( 2 + \mathrm { i } ) z = 0\), giving your answer in the form \(x + \mathrm { i } y\) where \(x\) and \(y\) are real.