Edexcel FP2 2008 June — Question 5

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Year2008
SessionJune
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicSecond order differential equations
TypeAsymptotic behavior for large values
DifficultyStandard +0.8 This is a standard second-order linear ODE with constant coefficients requiring complementary function (solving auxiliary equation with distinct real roots) and particular integral (polynomial form). Part (b) requires understanding asymptotic behavior. While methodical, it's a multi-step Further Maths question requiring several techniques, placing it moderately above average difficulty.
Spec4.10d Second order homogeneous: auxiliary equation method4.10e Second order non-homogeneous: complementary + particular integral

  1. Find, in terms of \(k\), the general solution of the differential equation $$\frac{d^2x}{dt^2} + 4\frac{dx}{dt} + 3x = kt + 5, \text{ where } k \text{ is a constant and } t > 0.$$ (7) For large values of \(t\), this general solution may be approximated by a linear function.
  2. Given that \(k = 6\), find the equation of this linear function.(2)(Total 9 marks)

\begin{enumerate}[label=(\alph*)]
\item Find, in terms of $k$, the general solution of the differential equation
$$\frac{d^2x}{dt^2} + 4\frac{dx}{dt} + 3x = kt + 5, \text{ where } k \text{ is a constant and } t > 0.$$ (7)

For large values of $t$, this general solution may be approximated by a linear function.

\item Given that $k = 6$, find the equation of this linear function.(2)(Total 9 marks)
\end{enumerate}

\hfill \mbox{\textit{Edexcel FP2 2008 Q5}}