3 years ago

2cos^2A-cos2A-1=0 Help

Mathematics

1 answer:

kondor19780726 [428]3 years ago

8 0

Answer:

steps below

Step-by-step explanation:

Are you going to solve the value of A or just a proof the equation

cos 2A = cos² A - sin² A

2cos²A-cos2A-1 = 2cos²A - (cos² A - sin² A) - 1 = cos² A + sin² A - 1

2cos²A-cos2A-1 = 1 - 1 = 0

A: 90° or 270° or 450° .....

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Step-by-step explanation:

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Lady bird [3.3K]

Answer:

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Step-by-step explanation:

Given the expression

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