9709 P32 - Jun 2011 - Q4
1865
The diagram shows a semicircle ACB with centre O and radius r. The tangent at C meets AB produced at T. The angle BOC is x radians. The area of the shaded region is equal to the area of the semicircle.
(i) Show that x satisfies the equation \(\tan x = x + \pi\).
(ii) Use the iterative formula \(x_{n+1} = \arctan(x_n + \pi)\) to determine x correct to 2 decimal places. Give the result of each iteration to 4 decimal places.
