Understanding the Unit Circle and Trigonometric Functions

What is the defining characteristic of a unit circle?

• It has a radius of two.

• It is centered at the origin.

• It is a square.

• It has a radius of one.

How do you form a triangle in the unit circle?

• By connecting the terminal arm to the Y-axis.

• By connecting the terminal arm to the X-axis.

• By drawing a line parallel to the Y-axis.

• By drawing a line parallel to the X-axis.

What does the X-coordinate of a point on the unit circle represent?

• The length of the hypotenuse.

• The sine of the angle.

• The tangent of the angle.

• The cosine of the angle.

What is a reference angle?

• The angle between the terminal arm and the Y-axis.

• The angle between the terminal arm and the X-axis.

• The angle between the hypotenuse and the X-axis.

• The angle between the hypotenuse and the Y-axis.

In the unit circle, what does the Y-coordinate represent?

• The secant of the angle.

• The sine of the angle.

• The tangent of the angle.

• The cosine of the angle.

What is the hypotenuse in a triangle formed in the unit circle?

• The X-coordinate.

• The tangent of the angle.

• The radius of the circle.

• The Y-coordinate.

How is cosine theta derived in the unit circle?

• As the hypotenuse over adjacent.

• As the opposite over hypotenuse.

• As the hypotenuse over opposite.

• As the adjacent over hypotenuse.

What is the sine of a 30-degree angle in the unit circle?

• 1

• 0.5

• 0.707

• 0.866

What is the cosine of a 30-degree angle in the unit circle?

• 0.707

• 0.866

• 1

• 0.5

How do you find the coordinates of a point on the unit circle for a given angle?

• By using the cotangent and cosecant functions.

• By using the sine and cosine functions.

• By using the sine and tangent functions.

• By using the tangent and secant functions.