Edexcel C3 — Question 1 10 marks

Exam BoardEdexcel
ModuleC3 (Core Mathematics 3)
Marks10
PaperDownload PDF ↗
TopicChain Rule
TypeFind curve equation from derivative
DifficultyModerate -0.3 This is a straightforward integration and differentiation question requiring standard techniques: differentiating a sum of powers (including negative powers), integrating to find f(x) using the constant of integration, and proving monotonicity by showing f'(x) > 0. All parts are routine C3 calculus with no problem-solving insight needed, making it slightly easier than average.
Spec1.07i Differentiate x^n: for rational n and sums1.07o Increasing/decreasing: functions using sign of dy/dx1.08b Integrate x^n: where n != -1 and sums

The function f, defined for \(x \in \mathbb{R}, x > 0\), is such that $$f'(x) = x^2 - 2 + \frac{1}{x^2}.$$
  1. Find the value of \(f''(x)\) at \(x = 4\). [3]
  2. Given that \(f(3) = 0\), find \(f(x)\). [4]
  3. Prove that \(f\) is an increasing function. [3]

The function f, defined for $x \in \mathbb{R}, x > 0$, is such that
$$f'(x) = x^2 - 2 + \frac{1}{x^2}.$$

\begin{enumerate}[label=(\alph*)]
\item Find the value of $f''(x)$ at $x = 4$. [3]
\item Given that $f(3) = 0$, find $f(x)$. [4]
\item Prove that $f$ is an increasing function. [3]
\end{enumerate}

\hfill \mbox{\textit{Edexcel C3  Q1 [10]}}