Trigonometric Functions and Identities

The video tutorial explains how to use double angle identities to simplify and evaluate trigonometric expressions. It covers three examples: simplifying cosine squared minus sine squared, using the double angle identity for sine, and applying the cosine double angle identity. Each example is verified using the unit circle, demonstrating the practical application of these identities in trigonometry.

What is the purpose of using double angle identities in this video?

• To find the derivative of functions

• To calculate integrals

• To solve quadratic equations

• To simplify and evaluate trigonometric expressions

What is the result of simplifying cosine squared A minus sine squared A?

• Cosine of 2A

• Sine of 2A

• Secant of 2A

• Tangent of 2A

If A equals pi/12, what is cosine of 2A?

• Secant of pi/6

• Tangent of pi/6

• Sine of pi/6

• Cosine of pi/6

What is the cosine of a 30-degree angle?

• 1/2

• Square root of 3 divided by 2

• Square root of 2 divided by 2

• 1

Which identity is used for the second expression involving 2 cosine of pi/4 times cosine pi/4?

• Secant of 2A

• Sine of 2A

• Cosine of 2A

• Tangent of 2A

What is the value of sine of pi/2?

• Square root of 2 divided by 2

• 1

• 0

• -1

What is the simplified form of 2 cosine squared pi/2 minus 1?

• Sine of pi

• Secant of pi

• Cosine of pi

• Tangent of pi

What is the cosine of pi?

• -1

• 1

• 0

• Square root of 2 divided by 2

How can you verify the cosine of pi on the unit circle?

• By checking the x-coordinate

• By checking the y-coordinate

• By checking the radius

• By checking the angle