Pre-U Pre-U 9794/1 2013 November — Question 10

Exam BoardPre-U
ModulePre-U 9794/1 (Pre-U Mathematics Paper 1)
Year2013
SessionNovember
TopicTangents, normals and gradients
TypeDetermine nature of stationary points
DifficultyModerate -0.3 This is a straightforward differentiation question requiring the quotient rule and basic stationary point analysis. Part (i) is routine calculation with a given answer to verify. Part (ii) requires finding where dy/dx = 0 and using the second derivative test, all standard techniques with no conceptual challenges or novel insights required.
Spec1.07j Differentiate exponentials: e^(kx) and a^(kx)1.07l Derivative of ln(x): and related functions1.07n Stationary points: find maxima, minima using derivatives1.07o Increasing/decreasing: functions using sign of dy/dx1.07q Product and quotient rules: differentiation

10 A curve has equation \(y = \frac { \mathrm { e } ^ { x } } { x ^ { 2 } }\). Show that
  1. the gradient of the curve at \(x = 1\) is - e ,
  2. there is a stationary point at \(x = 2\) and determine its nature.

10 A curve has equation $y = \frac { \mathrm { e } ^ { x } } { x ^ { 2 } }$. Show that\\
(i) the gradient of the curve at $x = 1$ is - e ,\\
(ii) there is a stationary point at $x = 2$ and determine its nature.

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