AQA FP3 2013 January — Question 1 6 marks

Exam BoardAQA
ModuleFP3 (Further Pure Mathematics 3)
Year2013
SessionJanuary
Marks6
PaperDownload PDF ↗
TopicFixed Point Iteration
TypeApply basic Euler method for differential equations
DifficultyStandard +0.3 This is a straightforward application of two standard numerical methods (Euler's method and midpoint method) with given formulas. Students simply substitute values into provided formulas with no derivation, problem-solving, or conceptual insight required. The arithmetic is routine, making this slightly easier than average for Further Maths FP3.
Spec1.09c Simple iterative methods: x_{n+1} = g(x_n), cobweb and staircase diagrams

1 It is given that \(y ( x )\) satisfies the differential equation $$\frac { \mathrm { d } y } { \mathrm {~d} x } = \mathrm { f } ( x , y )$$ where $$\mathrm { f } ( x , y ) = \sqrt { 2 x + y }$$ and $$y ( 3 ) = 5$$
  1. Use the Euler formula $$y _ { r + 1 } = y _ { r } + h \mathrm { f } \left( x _ { r } , y _ { r } \right)$$ with \(h = 0.2\), to obtain an approximation to \(y ( 3.2 )\), giving your answer to four decimal places.
  2. Use the formula $$y _ { r + 1 } = y _ { r - 1 } + 2 h \mathrm { f } \left( x _ { r } , y _ { r } \right)$$ with your answer to part (a), to obtain an approximation to \(y ( 3.4 )\), giving your answer to three decimal places.

1 It is given that $y ( x )$ satisfies the differential equation

$$\frac { \mathrm { d } y } { \mathrm {~d} x } = \mathrm { f } ( x , y )$$

where

$$\mathrm { f } ( x , y ) = \sqrt { 2 x + y }$$

and

$$y ( 3 ) = 5$$
\begin{enumerate}[label=(\alph*)]
\item Use the Euler formula

$$y _ { r + 1 } = y _ { r } + h \mathrm { f } \left( x _ { r } , y _ { r } \right)$$

with $h = 0.2$, to obtain an approximation to $y ( 3.2 )$, giving your answer to four decimal places.
\item Use the formula

$$y _ { r + 1 } = y _ { r - 1 } + 2 h \mathrm { f } \left( x _ { r } , y _ { r } \right)$$

with your answer to part (a), to obtain an approximation to $y ( 3.4 )$, giving your answer to three decimal places.
\end{enumerate}

\hfill \mbox{\textit{AQA FP3 2013 Q1 [6]}}