OCR Further Pure Core AS 2023 June — Question 8

Exam BoardOCR
ModuleFurther Pure Core AS (Further Pure Core AS)
Year2023
SessionJune
TopicComplex Numbers Arithmetic
TypeLinear equations in z and z*

8
  1. Solve the equation \(\omega + 2 + 7 \mathrm { i } = 3 \omega ^ { * } - \mathrm { i }\).
  2. Prove algebraically that, for non-zero \(z , z = - z ^ { * }\) if and only if \(z\) is purely imaginary.
  3. The complex numbers \(z\) and \(z ^ { * }\) are represented on an Argand diagram by the points \(A\) and \(B\) respectively.
    1. State, for any \(z\), the single transformation which transforms \(A\) to \(B\).
    2. Use a geometric argument to prove that \(z = z ^ { * }\) if and only if \(z\) is purely real.