Edexcel FP2 — Question 8 14 marks

Exam BoardEdexcel
ModuleFP2 (Further Pure Mathematics 2)
Marks14
PaperDownload PDF ↗
TopicSecond order differential equations
TypeResonance cases requiring modified PI
DifficultyChallenging +1.2 This is a standard Further Maths FP2 second-order differential equation question with resonance. While it requires multiple techniques (finding particular integral with given form, complementary function, applying initial conditions, sketching), each step follows well-established procedures taught in FP2. The resonance case (auxiliary equation roots match forcing frequency) adds some complexity beyond basic C4 differential equations, but this is routine material for Further Maths students. The 14 marks reflect length rather than exceptional difficulty.
Spec4.10e Second order non-homogeneous: complementary + particular integral

  1. Find the value of \(z\) for which \(y = zx \sin 5x\) is a particular integral of the differential equation $$\frac{d^2 y}{dx^2} + 25y = 3 \cos 5x.$$ [4]
  2. Using your answer to part (a), find the general solution of the differential equation $$\frac{d^2 y}{dx^2} + 25y = 3 \cos 5x.$$ [3]
Given that at \(x = 0\), \(y = 0\) and \(\frac{dy}{dx} = 5\),
  1. find the particular solution of this differential equation, giving your solution in the form \(y = f(x)\). [5]
  2. Sketch the curve with equation \(y = f(x)\) for \(0 \leq x \leq \pi\). [2]

\begin{enumerate}[label=(\alph*)]
\item Find the value of $z$ for which $y = zx \sin 5x$ is a particular integral of the differential equation
$$\frac{d^2 y}{dx^2} + 25y = 3 \cos 5x.$$ [4]
\item Using your answer to part (a), find the general solution of the differential equation
$$\frac{d^2 y}{dx^2} + 25y = 3 \cos 5x.$$ [3]
\end{enumerate}

Given that at $x = 0$, $y = 0$ and $\frac{dy}{dx} = 5$,

\begin{enumerate}[label=(\alph*)]
\setcounter{enumi}{2}
\item find the particular solution of this differential equation, giving your solution in the form $y = f(x)$. [5]
\item Sketch the curve with equation $y = f(x)$ for $0 \leq x \leq \pi$. [2]
\end{enumerate}

\hfill \mbox{\textit{Edexcel FP2  Q8 [14]}}