2023 IGCSE Additional Mathematics May/June 0606/23 Q8

2023 IGCSE Additional Mathematics May/June 0606/23 Q8

14 marks
  1. The functions \(\mathrm{f}\) and \(\mathrm{g}\) are defined by
    \(\mathrm{f}(x)=\sec x\qquad\text{for}\hspace{0.5em}\dfrac{\pi}{2}<x<\dfrac{3\pi}{2}\)
    \(\mathrm{g}(x)=3\left(x^2-1\right)\qquad\text{for all real}\hspace{0.5em}x.\)
    1. Find the range of \(\mathrm{f}\).[1]
    2. Solve the equation \(\mathrm{f}^{-1}(x)=\dfrac{2\pi}{3}\).[3]
    3. Given that \(\mathrm{gf}\) exists, state the domain of \(\mathrm{gf}\).[1]
    4. Solve the equation \(\mathrm{gf}(x)=1\).[5]
  2. The function \(\mathrm{h}\) is defined by \(\mathrm{h}(x)=\ln(4-x)\) for \(x<4\). Sketch the graph of \(y=\mathrm{h}(x)\) and hence sketch the graph of \(y=\mathrm{h}^{-1}(x)\). Show the position of any asymptotes and any points of intersection with the coordinate axes.[4]

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:(a)(i) \(\mathrm{f}(x)\le-1\) (ii) \(x=-2\) (iii) \(\dfrac{\pi}{2}<x<\dfrac{3\pi}{2}\) (iv) \(x=\dfrac{5\pi}{6}\) or \(x=\dfrac{7\pi}{6}\) (b) Sketch shown; \(\mathrm{h}\): intercepts \((0,\ln4)\) and \((3,0)\), asymptote \(x=4\); \(\mathrm{h}^{-1}\): intercepts \((0,3)\) and \((\ln4,0)\), asymptote \(y=4\)

Need help? Join our JC Math tuition classes.

Learn more