i. Using the expansion of cos(3x x) and cos(3x + x), prove that ii. Hence show that -~ (cos 2x - cos 4x) = sin 3x sin.x.
Chapter 5, Review Exercises #15
i. Using the expansion of cos(3x − x) and cos(3x + x), prove that 
ii. Hence show that
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) We can start by expanding cos(3x - x) and cos(3x + x) using the angle addition formula for cosine: …View the full answer
Related Book For 
Cambridge International AS & A Level Mathematics Pure Mathematics 2 & 3 Coursebook
1st Edition
Authors: Sue Pemberton, Julianne Hughes, Julian Gilbey
ISBN: 9781108407199