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lovemake1

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## Homework Statement

solve the following equation for x in the interval [0,2pi)

2Cos^2(2x) + 1 = 3Cos(2x)

## Homework Equations

Cos(2x) = 2Cos^2 (x) - 1

## The Attempt at a Solution

2Cos^2(2x) + 1 = 3Cos(2x)

2Cos(2x)Cos(2x) + 1 = 3Cos(2x)

2Cos(2x) + 1 = 3

2(2Cos^2 (x) - 1) - 2 =0

4Cos^2 (x) - 2 - 2 = 0

4cos^2 (x) = 4

Cos^2 (x) = 1

Cosx = 1

x = 0 is this right?

please correct me if i messed up thanks,

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