AQA FP1 2010 June — Question 1 6 marks

Exam BoardAQA
ModuleFP1 (Further Pure Mathematics 1)
Year2010
SessionJune
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicVariable acceleration (1D)
TypeNumerical methods for differential equations (step-by-step)
DifficultyModerate -0.5 This is a straightforward numerical methods question requiring Euler's method with given step size and initial conditions. While it involves multiple iterations (3 steps), the arithmetic is simple (adding 1 + x³ values), and the method is mechanical with no conceptual challenges. It's easier than average because it's purely procedural application of a standard algorithm, though not trivial since it requires careful arithmetic across multiple steps.
Spec1.07t Construct differential equations: in context1.09c Simple iterative methods: x_{n+1} = g(x_n), cobweb and staircase diagrams

1 A curve passes through the point ( 1,3 ) and satisfies the differential equation $$\frac { \mathrm { d } y } { \mathrm {~d} x } = 1 + x ^ { 3 }$$ Starting at the point ( 1,3 ), use a step-by-step method with a step length of 0.1 to estimate the \(y\)-coordinate of the point on the curve for which \(x = 1.3\). Give your answer to three decimal places.
(No credit will be given for methods involving integration.)

Question 1:
AnswerMarks Guidance
Answer/WorkingMark Guidance
At \(x=1\): \(\frac{dy}{dx} = 1 + 1^3 = 2\)M1 Correct use of step-by-step method
\(y(1.1) = 3 + 0.1 \times 2 = 3.2\)A1 Correct first step
At \(x=1.1\): \(\frac{dy}{dx} = 1 + (1.1)^3 = 2.331\)M1 Correct evaluation of derivative at new point
\(y(1.2) = 3.2 + 0.1 \times 2.331 = 3.4331\)A1 Correct second step
At \(x=1.2\): \(\frac{dy}{dx} = 1 + (1.2)^3 = 2.728\)
\(y(1.3) = 3.4331 + 0.1 \times 2.728 = 3.706\)A1 Answer to 3 d.p.
Correct method shown throughoutB1 All three steps attempted correctly
# Question 1:

| Answer/Working | Mark | Guidance |
|---|---|---|
| At $x=1$: $\frac{dy}{dx} = 1 + 1^3 = 2$ | M1 | Correct use of step-by-step method |
| $y(1.1) = 3 + 0.1 \times 2 = 3.2$ | A1 | Correct first step |
| At $x=1.1$: $\frac{dy}{dx} = 1 + (1.1)^3 = 2.331$ | M1 | Correct evaluation of derivative at new point |
| $y(1.2) = 3.2 + 0.1 \times 2.331 = 3.4331$ | A1 | Correct second step |
| At $x=1.2$: $\frac{dy}{dx} = 1 + (1.2)^3 = 2.728$ | | |
| $y(1.3) = 3.4331 + 0.1 \times 2.728 = 3.706$ | A1 | Answer to 3 d.p. |
| Correct method shown throughout | B1 | All three steps attempted correctly |

---
1 A curve passes through the point ( 1,3 ) and satisfies the differential equation

$$\frac { \mathrm { d } y } { \mathrm {~d} x } = 1 + x ^ { 3 }$$

Starting at the point ( 1,3 ), use a step-by-step method with a step length of 0.1 to estimate the $y$-coordinate of the point on the curve for which $x = 1.3$. Give your answer to three decimal places.\\
(No credit will be given for methods involving integration.)

\hfill \mbox{\textit{AQA FP1 2010 Q1 [6]}}