AQA Paper 3 2022 June — Question 10 2 marks

Exam BoardAQA
ModulePaper 3 (Paper 3)
Year2022
SessionJune
Marks2
TopicComposite & Inverse Functions

10 The function f is defined by $$f ( x ) = \frac { x ^ { 2 } + 10 } { 2 x + 5 }$$ where \(f\) has its maximum possible domain. The curve \(y = \mathrm { f } ( x )\) intersects the line \(y = x\) at the points \(P\) and \(Q\) as shown below.
\includegraphics[max width=\textwidth, alt={}, center]{6ad3bac9-bf08-443d-8be2-b0c26209ffe8-14_908_1125_685_459} 10
  1. State the value of \(x\) which is not in the domain of f . 10
  2. Explain how you know that the function f is many-to-one.
    10
    1. Show that the \(x\)-coordinates of \(P\) and \(Q\) satisfy the equation $$x ^ { 2 } + 5 x - 10 = 0$$ [2 marks]
      10
  3. (ii) Hence, find the exact \(x\)-coordinate of \(P\) and the exact \(x\)-coordinate of \(Q\).
    10
  4. Show that \(P\) and \(Q\) are stationary points of the curve. Fully justify your answer.
    10
  5. Using set notation, state the range of f .