OCR MEI C2 2008 June — Question 5 4 marks

Exam BoardOCR MEI
ModuleC2 (Core Mathematics 2)
Year2008
SessionJune
Marks4
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTangents, normals and gradients
TypeFind derivative of simple polynomial (integer powers)
DifficultyModerate -0.8 This is a straightforward numerical differentiation question using chord gradients. Part (i) requires simple substitution into y=2^x and calculating (y₂-y₁)/(x₂-x₁). Part (ii) tests understanding that a smaller interval gives better approximation—students just need to choose points closer to x=3. No calculus, proof, or problem-solving required; purely mechanical application of a basic concept.
Spec1.07a Derivative as gradient: of tangent to curve

In Fig. 5, A and B are the points on the curve \(y = 2^x\) with \(x\)-coordinates 3 and 3.1 respectively. \includegraphics{figure_5}
  1. Find the gradient of the chord AB. Give your answer correct to 2 decimal places. [2]
  2. Stating the points you use, find the gradient of another chord which will give a closer approximation to the gradient of the tangent to \(y = 2^x\) at A. [2]

In Fig. 5, A and B are the points on the curve $y = 2^x$ with $x$-coordinates 3 and 3.1 respectively.

\includegraphics{figure_5}

\begin{enumerate}[label=(\roman*)]
\item Find the gradient of the chord AB. Give your answer correct to 2 decimal places. [2]
\item Stating the points you use, find the gradient of another chord which will give a closer approximation to the gradient of the tangent to $y = 2^x$ at A. [2]
\end{enumerate}

\hfill \mbox{\textit{OCR MEI C2 2008 Q5 [4]}}