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What is cos2 A?

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Anonymous

12y ago
Updated: 3/16/2025

Cos(2A) = Cos(A + A)

Double Angle Indentity

Cos(A+A) = Cos(A)Cos(A) - Sin(A)Sin(A) =>

Cos^(2)[A] - SIn^(2)[A] =>

Cos^(2)[A] - (1 - Cos^(2)[A] =>

2Cos^(2)[A] - 1

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lenpollock

Lvl 16
1mo ago

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More answers

cos2A = cos^2A-sin^2A (2A means the double angle .. :|)

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Wiki User

12y ago
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