OCR MEI Further Numerical Methods Specimen — Question 2

Exam BoardOCR MEI
ModuleFurther Numerical Methods (Further Numerical Methods)
SessionSpecimen
TopicSign Change & Interval Methods
TypeInterval Bisection from Spreadsheet

2 The following spreadsheet printout shows the bisection method being applied to the equation \(\mathrm { f } ( x ) = 0\), where \(\mathrm { f } ( x ) = \mathrm { e } ^ { x } - x ^ { 2 } - 2\). Some values of \(\mathrm { f } ( x )\) are shown in columns B and D.
ABCDEFG
1a\(\mathrm { f } ( a )\)bf(b)\(( a + b ) / 2\)\(\mathrm { f } ( ( a + b ) / 2 )\)mpe
21-0.2817221.3890561.50.2316890.5
31-0.281721.50.2316891.25-0.0721570.25
41.25-0.072161.50.2316891.3750.0644520.125
51.25-0.072161.3750.0644521.3125-0.0072060.0625
61.3125-0.007211.3750.0644521.343750.0277280.03125
  1. The formula in cell A 3 is \(= \mathrm { IF } ( \mathrm { F } 2 > 0\), A2, E2). State the purpose of this formula.
  2. The formula in cell C 3 is \(= \mathrm { IF } ( \mathrm { F } 2 > 0 , \ldots , \ldots )\). What are the missing cell references?
  3. In which row is the magnitude of the maximum possible error (mpe) less than \(5 \times 10 ^ { - 7 }\) for the first time?