Edexcel FP3 — Question 22 7 marks

Exam BoardEdexcel
ModuleFP3 (Further Pure Mathematics 3)
Marks7
PaperDownload PDF ↗
TopicIntegration using inverse trig and hyperbolic functions
TypeStandard integral of 1/(a²+x²)
DifficultyStandard +0.8 This is a Further Maths question requiring completing the square followed by recognition and application of the inverse tangent integration formula. Part (a) is routine algebraic manipulation (3 marks), while part (b) requires knowing the standard result ∫1/(x²+a²)dx = (1/a)arctan(x/a) + c and careful substitution with exact arithmetic. The topic itself (inverse trig integration) is beyond standard A-level, and the multi-step nature with exact values pushes this above average difficulty, though it remains a fairly standard FP3 exercise rather than requiring deep insight.
Spec1.02e Complete the square: quadratic polynomials and turning points1.08h Integration by substitution

$$4x^2 + 4x + 17 \equiv (ax + b)^2 + c, \quad a > 0.$$
  1. Find the values of \(a\), \(b\) and \(c\). [3]
  2. Find the exact value of $$\int_{-0.5}^{1.5} \frac{1}{4x^2 + 4x + 17} \, dx.$$ [4]

$$4x^2 + 4x + 17 \equiv (ax + b)^2 + c, \quad a > 0.$$

\begin{enumerate}[label=(\alph*)]
\item Find the values of $a$, $b$ and $c$. [3]

\item Find the exact value of
$$\int_{-0.5}^{1.5} \frac{1}{4x^2 + 4x + 17} \, dx.$$ [4]
\end{enumerate}

\hfill \mbox{\textit{Edexcel FP3  Q22 [7]}}