Question 0111b

Equations and Inequalities
2011 Paper 1 Question 2 Variant

Question

It is given that f(x)=ax2+bx+c,{f(x)=ax^2+bx+c,} where a,b{a,b} and c{c} are constants.
(i)
Given that the curve with equation y=f(x){y=f(x)} passes through the points with coordinates (1.0,0.1),{(-1.0, -0.1),} (2.4,9.0){(2.4, 9.0)} and (4.0,17.7),{(4.0, 17.7),} find the values of a,b{a,b} and c.{c.} Give your answers correct to 3 decimal places.
[3]
(ii)
Find the set of values of x{x} for which f(x){f(x)} is a decreasing function.
[2]

Answer