Question 7 - A-Level Maths

Exam Board	AQA
Module	AS Paper 1 (AS Paper 1)
Year	2019
Session	June
Marks	6
Topic	Differentiation Applications
Type	Optimization with constraints

7 Given that $y \in \mathbb { R }$, prove that $$( 2 + 3 y ) ^ { 4 } + ( 2 - 3 y ) ^ { 4 } \geq 32$$ Fully justify your answer.
[0pt] [6 marks]