Question 4 - A-Level Maths

Exam Board	OCR MEI
Module	C2 (Core Mathematics 2)
Year	2008
Session	June
Topic	Differentiation Applications
Type	Increasing/decreasing intervals

4 Use calculus to find the set of values of \(x\) for which \(\mathrm { f } ( x ) = 12 x - x ^ { 3 }\) is an increasing function.