OCR H240/02 2017 Specimen — Question 2 7 marks

Exam BoardOCR
ModuleH240/02 (Pure Mathematics and Statistics)
Year2017
SessionSpecimen
Marks7
TopicStationary points and optimisation
TypeClassify nature of stationary points
DifficultyModerate -0.8 This is a straightforward calculus question requiring basic differentiation of polynomials, substitution to verify a stationary point, and using the second derivative test. All techniques are routine and mechanical with no problem-solving insight needed, making it easier than average but not trivial since it requires multiple steps and correct application of the second derivative test.
Spec1.07i Differentiate x^n: for rational n and sums1.07n Stationary points: find maxima, minima using derivatives1.07p Points of inflection: using second derivative

A curve has equation \(y = x^5 - 5x^4\).
  1. Find \(\frac{dy}{dx}\) and \(\frac{d^2y}{dx^2}\). [3]
  2. Verify that the curve has a stationary point when \(x = 4\). [2]
  3. Determine the nature of this stationary point. [2]

A curve has equation $y = x^5 - 5x^4$.

\begin{enumerate}[label=(\alph*)]
\item Find $\frac{dy}{dx}$ and $\frac{d^2y}{dx^2}$. [3]

\item Verify that the curve has a stationary point when $x = 4$. [2]

\item Determine the nature of this stationary point. [2]
\end{enumerate}

\hfill \mbox{\textit{OCR H240/02 2017 Q2 [7]}}