CAIE P2 2008 June — Question 6 7 marks

Exam BoardCAIE
ModuleP2 (Pure Mathematics 2)
Year2008
SessionJune
Marks7
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicDifferentiating Transcendental Functions
TypeFind stationary points - polynomial/exponential products
DifficultyModerate -0.3 This is a straightforward application of the product rule to find a stationary point, followed by a standard second derivative test. The algebra is simple (linear factor times exponential), and both parts are routine A-level calculus procedures requiring no problem-solving insight, making it slightly easier than average.
Spec1.07n Stationary points: find maxima, minima using derivatives1.07r Chain rule: dy/dx = dy/du * du/dx and connected rates

6 It is given that the curve \(y = ( x - 2 ) \mathrm { e } ^ { x }\) has one stationary point.
  1. Find the exact coordinates of this point.
  2. Determine whether this point is a maximum or a minimum point.

AnswerMarks
(i) Use product ruleM1*
Obtain correct derivative in any form, e.g. \((x - 1)e^x\)A1
Equate derivative to zero and solve for \(x\)M1* (dep)
Obtain \(x = 1\)A1
Obtain \(y = -e\)A1
[5]
(ii) Carry out a method for determining the nature of a stationary pointM1
Show that the point is a minimum point, with no errors seenA1
[2]
**(i)** Use product rule | M1* |
Obtain correct derivative in any form, e.g. $(x - 1)e^x$ | A1 |
Equate derivative to zero and solve for $x$ | M1* (dep) |
Obtain $x = 1$ | A1 |
Obtain $y = -e$ | A1 |
| [5] |

**(ii)** Carry out a method for determining the nature of a stationary point | M1 |
Show that the point is a minimum point, with no errors seen | A1 |
| [2] |
6 It is given that the curve $y = ( x - 2 ) \mathrm { e } ^ { x }$ has one stationary point.\\
(i) Find the exact coordinates of this point.\\
(ii) Determine whether this point is a maximum or a minimum point.

\hfill \mbox{\textit{CAIE P2 2008 Q6 [7]}}