Trigonometric Functions and Values

This video tutorial explains how to find the sine, cosine, and tangent of angles using the unit circle. It covers the concept of quadrantal angles and how to calculate trigonometric ratios at these angles. The tutorial also discusses the conditions under which trigonometric ratios become undefined, emphasizing the importance of recognizing these scenarios. By using x and y coordinates, the video simplifies the understanding of trigonometric functions and their applications.

What is the sine of 270 degrees using the unit circle?

• 1

• Undefined

• 0

• -1

Which coordinate is zero at 90 degrees on the unit circle?

• Neither x nor y

• x

• y

• Both x and y

At 180 degrees, what is the value of the cosine?

• 1

• Undefined

• 0

• -1

Why is the tangent undefined at 90 degrees?

• y is zero

• Neither x nor y is zero

• x is zero

• Both x and y are zero

What is the secant of 90 degrees?

• -1

• Undefined

• 0

• 1

At which angle is the cosine equal to 1?

• 360 degrees

• 270 degrees

• 180 degrees

• 90 degrees

What is the tangent of a horizontal terminal ray?

• -1

• Undefined

• 0

• 1

Which angles have a y-coordinate equal to zero?

• Multiples of 270 degrees

• Multiples of 180 degrees

• Multiples of 360 degrees

• Multiples of 90 degrees

What is the sine of 0 degrees?

• Undefined

• -1

• 0

• 1

Which trig ratio is the reciprocal of sine?

• Cosine

• Tangent

• Secant

• Cosecant