Edexcel F1 2021 June — Question 1

Exam BoardEdexcel
ModuleF1 (Further Pure Mathematics 1)
Year2021
SessionJune
TopicSign Change & Interval Methods
TypePure Newton-Raphson Application

1.(i) $$f ( x ) = x ^ { 3 } + 4 x - 6$$ (a)Show that the equation \(\mathrm { f } ( x ) = 0\) has a root \(\alpha\) in the interval[1,1.5]
(b)Taking 1.5 as a first approximation,apply the Newton Raphson process twice to \(\mathrm { f } ( x )\) to obtain an approximate value of \(\alpha\) .Give your answer to 3 decimal places. Show your working clearly.
(ii) $$g ( x ) = 4 x ^ { 2 } + x - \tan x$$ where \(x\) is measured in radians. The equation \(\mathrm { g } ( x ) = 0\) has a single root \(\beta\) in the interval[1.4,1.5]
Use linear interpolation on the values at the end points of this interval to obtain an approximation to \(\beta\) .Give your answer to 3 decimal places.