Edexcel FP2 — Question 7 12 marks

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Marks12
PaperDownload PDF ↗
TopicModulus function
TypeSketch modulus functions involving quadratic or other non-linear
DifficultyStandard +0.8 This is a Further Maths FP2 question requiring systematic case analysis of modulus equations and inequalities. Part (a) is routine, but parts (b) and (c) demand careful consideration of multiple cases (x² - a² positive/negative), solving resulting quadratics, and checking validity of solutions against case conditions. The algebraic manipulation is substantial and errors are easy to make, placing this moderately above average difficulty.
Spec1.02g Inequalities: linear and quadratic in single variable1.02l Modulus function: notation, relations, equations and inequalities

  1. Sketch the graph of \(y = |x^2 - a^2|\), where \(a > 1\), showing the coordinates of the points where the graph meets the axes. [2]
  2. Solve \(|x^2 - a^2| = a^2 - x\), \(a > 1\). [6]
  3. Find the set of values of \(x\) for which \(|x^2 - a^2| > a^2 - x\), \(a > 1\). [4]

\begin{enumerate}[label=(\alph*)]
\item Sketch the graph of $y = |x^2 - a^2|$, where $a > 1$, showing the coordinates of the points where the graph meets the axes. [2]
\item Solve $|x^2 - a^2| = a^2 - x$, $a > 1$. [6]
\item Find the set of values of $x$ for which $|x^2 - a^2| > a^2 - x$, $a > 1$. [4]
\end{enumerate}

\hfill \mbox{\textit{Edexcel FP2  Q7 [12]}}