Edexcel P3 2018 Specimen — Question 6

Exam BoardEdexcel
ModuleP3 (Pure Mathematics 3)
Year2018
SessionSpecimen
TopicComposite & Inverse Functions

  1. The functions f and g are defined by
$$\mathrm { f } : x \mapsto \mathrm { e } ^ { x } + 2 \quad x \in \mathbb { R }$$ $$\mathrm { g } : x \mapsto \ln x \quad x > 0$$
  1. State the range of f .
  2. Find \(\mathrm { fg } ( x )\), giving \(y\) our answer in its simplest form.
  3. Find the exact value of \(x\) for which \(\mathrm { f } ( 2 x + 3 ) = 6\)
  4. Find \(\mathrm { f } ^ { - 1 }\) stating its domain.
  5. On the same axes sketch the curves with equation \(y = \mathrm { f } ( x )\) and \(y = \mathrm { f } ^ { - 1 } ( x )\), giving the coordinates of all the points where the curves cross the axes.