Learn how to evaluate the angle in radians for cosine

The video tutorial explains how to determine the cosine of an angle based on its position in a circle, specifically focusing on angles in the second quadrant where cosine is negative. It demonstrates the application of a formula involving cosine of U/2, reducing expressions, and simplifying results using the distributive property. The tutorial also compares the current problem with previous ones to highlight differences and similarities in approach.

In which quadrant is the angle located if its cosine is negative?

• Third quadrant

• Second quadrant

• Fourth quadrant

• First quadrant

What is the simplified form of U if U/2 equals 7π/12?

• 14π/12

• 7π/6

• π/2

• π/3

What is the cosine of 7π/6?

• Negative square root of 2

• Positive square root of 2

• Negative square root of 3

• Positive square root of 3

Which property is applied to simplify the expression 2 - sqrt(3)/4?

• Associative property

• Distributive property

• Commutative property

• Identity property

How is the square root in the numerator and denominator handled in the final expression?

• It is divided by 2

• It is multiplied by 2

• It is rewritten as multiplication

• It is left unchanged