Edexcel F1 2022 June — Question 4

Exam BoardEdexcel
ModuleF1 (Further Pure Mathematics 1)
Year2022
SessionJune
TopicRoots of polynomials

4. $$f ( z ) = 2 z ^ { 4 } - 19 z ^ { 3 } + A z ^ { 2 } + B z - 156$$ where \(A\) and \(B\) are constants.
The complex number \(5 - \mathrm { i }\) is a root of the equation \(\mathrm { f } ( \mathrm { z } ) = 0\)
  1. Write down another complex root of this equation.
  2. Solve the equation \(\mathrm { f } ( \mathrm { z } ) = 0\) completely.
  3. Determine the value of \(A\) and the value of \(B\).