Edexcel FP2 — Question 7 13 marks

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Marks13
PaperDownload PDF ↗
TopicSecond order differential equations
TypeResonance cases requiring modified PI
DifficultyStandard +0.8 This is a Further Maths FP2 question on second-order differential equations with repeated roots (auxiliary equation gives m=3 twice), requiring recognition that the standard particular integral fails and needs modification to te^(3t). The question involves finding complementary function, particular integral with the correct form, and applying initial conditions. While systematic, it requires understanding of the repeated root case and careful algebraic manipulation across multiple steps, placing it moderately above average difficulty.
Spec4.10e Second order non-homogeneous: complementary + particular integral

  1. Find the value of \(z\) for which \(z^{2e^x}\) is a particular integral of the differential equation $$\frac{d^2 y}{dt^2} - 6 \frac{dy}{dt} + 9y = 6e^{3t}, \quad t \geq 0$$ [5]
  2. Hence find the general solution of this differential equation. [3]
Given that when \(t = 0\), \(y = 5\) and \(\frac{dy}{dt} = 4\)
  1. find the particular solution of this differential equation, giving your solution in the form \(y = f(t)\). [5]

\begin{enumerate}[label=(\alph*)]
\item Find the value of $z$ for which $z^{2e^x}$ is a particular integral of the differential equation
$$\frac{d^2 y}{dt^2} - 6 \frac{dy}{dt} + 9y = 6e^{3t}, \quad t \geq 0$$ [5]
\item Hence find the general solution of this differential equation. [3]
\end{enumerate}

Given that when $t = 0$, $y = 5$ and $\frac{dy}{dt} = 4$

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item find the particular solution of this differential equation, giving your solution in the form $y = f(t)$. [5]
\end{enumerate}

\hfill \mbox{\textit{Edexcel FP2  Q7 [13]}}