Question: a. By writing 3 as 2 + , show that cos 3 4 cos 3 3 cos . b. Hence, or otherwise,

a. By writing 3θ as 2θ + θ, show that cos 3θ ≡ 4 cos3 θ − 3 cos θ.

b. Hence, or otherwise, for 0 < θ < π, solve 6 cos θ − 8 cosθ + 1 = 0 giving your answer in terms of π.

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a To show the trigonometric identity cos 3 4 cos3 3 cos using the angle addition formula well write ... View full answer

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