OCR MEI C4 2007 January — Question 6 8 marks

Exam BoardOCR MEI
ModuleC4 (Core Mathematics 4)
Year2007
SessionJanuary
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicPartial Fractions
TypePartial fractions for differential equations
DifficultyStandard +0.3 This is a straightforward two-part question combining routine partial fractions decomposition with separation of variables for a differential equation. Part (i) is standard textbook practice, and part (ii) follows a predictable method (separate variables, integrate using the partial fractions result, apply initial condition). The 'show that' format removes problem-solving challenge since students know the target answer. Slightly above average difficulty only due to the multi-step integration and algebraic manipulation required.
Spec1.02y Partial fractions: decompose rational functions1.08k Separable differential equations: dy/dx = f(x)g(y)1.08l Interpret differential equation solutions: in context

6
  1. Express \(\frac { 1 } { ( 2 x + 1 ) ( x + 1 ) }\) in partial fractions.
  2. A curve passes through the point \(( 0,2 )\) and satisfies the differential equation $$\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { y } { ( 2 x + 1 ) ( x + 1 ) }$$ Show by integration that \(y = \frac { 4 x + 2 } { x + 1 }\). Section B (36 marks)

(i) Express \(\frac{1}{(2x-1)(x-1)}\) in partial fractions. [3]
(ii) A curve passes through the point \((0, 2)\) and satisfies the differential equation
\[\frac{dy}{dx} = \frac{y}{(2x-1)(x-1)}\]
Show by integration that \(y = \frac{4x-2}{x-1}\). [5]
(i) Express $\frac{1}{(2x-1)(x-1)}$ in partial fractions. [3]

(ii) A curve passes through the point $(0, 2)$ and satisfies the differential equation
$$\frac{dy}{dx} = \frac{y}{(2x-1)(x-1)}$$

Show by integration that $y = \frac{4x-2}{x-1}$. [5]
6 (i) Express $\frac { 1 } { ( 2 x + 1 ) ( x + 1 ) }$ in partial fractions.\\
(ii) A curve passes through the point $( 0,2 )$ and satisfies the differential equation

$$\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { y } { ( 2 x + 1 ) ( x + 1 ) }$$

Show by integration that $y = \frac { 4 x + 2 } { x + 1 }$.

Section B (36 marks)\\

\hfill \mbox{\textit{OCR MEI C4 2007 Q6 [8]}}