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Numerical Methods

Numerical Methods

Medium
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Question 4
f(x)=−x3+3x2−1. f(x) = -x^3 + 3x^2 - 1. f(x)=−x3+3x2−1.
a.

Show that the equation f(x)=0f(x) = 0f(x)=0 can be rewritten as

x=(13−x). x = \sqrt{\left(\frac{1}{3-x}\right)}. x=(3−x1​)​.
[3]
b.

Starting with x1=0.6x_1 = 0.6x1​=0.6, use the iteration

xn+1=(13−xn) x_{n+1} = \sqrt{\left(\frac{1}{3-x_n}\right)} xn+1​=(3−xn​1​)​

to calculate the values of x2x_2x2​, x3 x_3\,x3​ and x4x_4x4​, giving all your answers to 4 decimal places.

[3]
c.

Show that x=0.653x = 0.653x=0.653 is a root of f(x)=0f(x) = 0f(x)=0 correct to 3 decimal places.

[3]
Markscheme

Numerical Methods Questions

  1. A Level
  2. /Old Maths
  3. /Numerical Methods

7 exam-style questions on Edexcel A Level Old Maths Numerical Methods. Each one has a worked solution and a mark scheme showing where the marks go.

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