How to find the exact value using the half angle formula for cosine

The video tutorial covers evaluating angles using sum, difference, and double angle formulas, with a focus on the half angle formula. It explains how to apply the half angle formula to find exact values, particularly for cosine, and demonstrates simplification techniques. The tutorial also includes administrative announcements about rescheduled meetings and student support services.

What is the alternative method mentioned for evaluating angles when the sum or difference method is not applicable?

• Double angle formula

• Triple angle formula

• Quadrant method

• Half angle formula

In the half angle formula, how do you determine whether to use the positive or negative sign?

• By the type of angle (acute or obtuse)

• By the quadrant in which the angle lies

• By the sum of the angles

• By the size of the angle

What is the first step in using the half angle formula for cosine?

• Multiply by 2

• Find the sine of the angle

• Use the sum of angles

• Determine the angle to plug into the formula

What is the cosine of 30 degrees as used in the example?

• 1/2

• sqrt(3)/2

• 1

• 0

What is the final simplified expression for the example given in the video?

• sqrt(1 + sqrt(3)/2)

• 1/2

• sqrt(3)/2

• 1 + sqrt(3)/2

What mistake was corrected regarding the multiplication in the example?

• Multiplying by 2/2

• Multiplying by 4/4

• Multiplying by 1

• Multiplying by 3/3

What should you do if you are failing your first semester course according to the announcement?

• Ignore it

• See your guidance counselor

• Drop the course

• Retake the course next year