AQA FP2 2012 January — Question 6 8 marks

Exam BoardAQA
ModuleFP2 (Further Pure Mathematics 2)
Year2012
SessionJanuary
Marks8
PaperDownload PDF ↗
TopicIntegration using inverse trig and hyperbolic functions
TypeStandard integral of 1/√(a²-x²)
DifficultyStandard +0.3 This is a straightforward Further Maths question requiring completing the square (routine algebraic manipulation) followed by a standard inverse trig integral with substitution. While it involves Further Maths content, the techniques are mechanical and well-practiced, making it slightly easier than average overall but standard for FP2.
Spec4.08h Integration: inverse trig/hyperbolic substitutions

6
  1. Express \(7 + 4 x - 2 x ^ { 2 }\) in the form \(a - b ( x - c ) ^ { 2 }\), where \(a , b\) and \(c\) are integers.
  2. By means of a suitable substitution, or otherwise, find the exact value of $$\int _ { 1 } ^ { \frac { 5 } { 2 } } \frac { \mathrm {~d} x } { \sqrt { 7 + 4 x - 2 x ^ { 2 } } }$$

6
\begin{enumerate}[label=(\alph*)]
\item Express $7 + 4 x - 2 x ^ { 2 }$ in the form $a - b ( x - c ) ^ { 2 }$, where $a , b$ and $c$ are integers.
\item By means of a suitable substitution, or otherwise, find the exact value of

$$\int _ { 1 } ^ { \frac { 5 } { 2 } } \frac { \mathrm {~d} x } { \sqrt { 7 + 4 x - 2 x ^ { 2 } } }$$
\end{enumerate}

\hfill \mbox{\textit{AQA FP2 2012 Q6 [8]}}