Double Angle (Cosine)

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Double Angle (Cosine)

The Formula

cos(2θ) = cos²(θ) - sin²(θ)

Variables & Symbols

θ, A, B

Angles

When to Use This Formula

  • Simplifying expressions
  • Solving equations

Worked Examples

Example 1

Problem:

Example

Solution: Result

Step-by-Step:

1

Apply formula

Common Mistakes to Avoid

  • Sign errors
  • Incorrect substitution

Real-World Applications

1

Physics

2

Engineering

3

Navigation

Practice Problems

Problem 1: Practice

Show Answer

Answer: Answer

Related Formulas

trig identities

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