How to evaluate the half angle for sine in radians

The video tutorial explains how to evaluate the sine of π/2 by identifying the angle's location in the first quadrant, where sine is positive. It introduces a formula involving sine and cosine, and demonstrates solving for U. The tutorial simplifies the expression using radicals and reviews algebra concepts, providing insights into common answer formats.

In which quadrant is the angle π/12 located, and what is the sign of sine in that quadrant?

• Quadrant 1, positive

• Quadrant 2, negative

• Quadrant 3, negative

• Quadrant 4, positive

If U/2 equals π/12, what is the value of U?

• π/2

• π/3

• π/6

• π/4

What is the cosine of π/6?

• sqrt 3/2

• 0

• sqrt 2/2

• 1/2

How can you simplify the expression 1 - sqrt 3/2 divided by 2?

• Multiply by 2 on the top and bottom

• Add 2 to the numerator

• Subtract 2 from the denominator

• Divide the numerator by 2

What is the common way to write answers involving radicals in multiple-choice tests?

• Without separating the square roots

• By adding a constant to the expression

• With radicals inside radicals

• By separating the square roots of the numerator and denominator