2021 TJC P2 Q1

2021 TJC P2 Q1

7 marks
Prelims

The functions \(\mathrm{f}\) and \(\mathrm{g}\) are defined by

\(\mathrm{f}:x\mapsto 2-{{\left( x-2 \right)}^{2}}\) for \(x\le 0\), \(x\in \mathbb{R}\),

and

\(\mathrm{g}:x\mapsto \left\{ \begin{matrix} 4\,\,\,\,\,\,\,\,\,\,\,\,\,\,\mathrm{for}\,\,\,x\ge 3,\,x\in \mathbb{R} \\ x+1\,\,\,\,\,\,\,\mathrm{for}\,\,\,x<3,x\in \mathbb{R} \\ \end{matrix} \right.\)

  1. Define \({{\mathrm{f}}^{-1}}\) in a similar form.[3]
  2. Explain why \(\mathrm{g}\) does not have an inverse.[2]
  3. Find the range of values of \(\alpha \) such that \(\mathrm{fg}\left( \alpha \right)\) exists.[2]

Video Solution:

Video Solution

Video solution locked

A free account saves your progress; this video needs tuition enrolment.

Solution:

Solution locked

680+ questions here come with free worked solutions. A free account saves your questions and progress; this one needs tuition enrolment.

Create a free account to practise similar questions.

Answer:(i) \(\mathrm f^{-1}:x\mapsto2-\sqrt{2-x}\), \(x\leq-2\) (ii) \(\mathrm g\) is not one-to-one (iii) \(\alpha\leq-1\)

Need help? Join our JC Math tuition classes.

Learn more