Edexcel C4 2013 June — Question 6 11 marks

Exam BoardEdexcel
ModuleC4 (Core Mathematics 4)
Year2013
SessionJune
Marks11
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicPartial Fractions
TypePartial fractions with linear factors – decompose and integrate (indefinite)
DifficultyModerate -0.3 Part (i)(a) is a standard partial fractions decomposition with distinct linear factors requiring routine algebraic manipulation. Part (i)(b) follows immediately by integrating the partial fractions to get logarithms. Part (ii) requires recognizing the substitution u³=x, factoring the denominator, and integrating—more steps but still a textbook application of C4 techniques. Overall slightly easier than average due to straightforward setup and standard methods.
Spec1.02y Partial fractions: decompose rational functions1.08c Integrate e^(kx), 1/x, sin(kx), cos(kx)1.08h Integration by substitution1.08j Integration using partial fractions

    1. Express \(\frac{7x}{(x + 3)(2x - 1)}\) in partial fractions. [3]
    2. Given that \(x > \frac{1}{2}\), find $$\int \frac{7x}{(x + 3)(2x - 1)} \, dx$$ [3]
  1. Using the substitution \(u^3 = x\), or otherwise, find $$\int \frac{1}{x + x^3} \, dx, \quad x > 0$$ [5]

\begin{enumerate}[label=(\roman*)]
\item \begin{enumerate}[label=(\alph*)]
\item Express $\frac{7x}{(x + 3)(2x - 1)}$ in partial fractions.
[3]

\item Given that $x > \frac{1}{2}$, find
$$\int \frac{7x}{(x + 3)(2x - 1)} \, dx$$
[3]
\end{enumerate}

\item Using the substitution $u^3 = x$, or otherwise, find
$$\int \frac{1}{x + x^3} \, dx, \quad x > 0$$
[5]
\end{enumerate}

\hfill \mbox{\textit{Edexcel C4 2013 Q6 [11]}}