Mastering the Unit Circle: Trig Values A to Z

PreAlgebra Grades High School 16:40 Video

Lesson Description

A comprehensive lesson practicing finding trigonometric values (sine, cosine, tangent, cosecant, secant, cotangent) for various angles in both degrees and radians, covering 26 examples.

Video Resource

Unit Circle Practice A to Z (Degrees & Radians)

Mario's Math Tutoring

Duration: 16:40
Watch on YouTube

Key Concepts

  • Unit Circle
  • Radians and Degrees
  • Trigonometric Functions (sin, cos, tan, csc, sec, cot)
  • Reference Angles
  • Coordinate Geometry

Learning Objectives

  • Students will be able to convert between degree and radian measures.
  • Students will be able to identify the location of angles on the unit circle.
  • Students will be able to determine the values of trigonometric functions for given angles using the unit circle and reference angles.
  • Students will be able to evaluate trigonometric functions, including reciprocal functions, for angles in all four quadrants.

Educator Instructions

  • Introduction (5 mins)
    Begin by reviewing the definition of the unit circle and its relationship to trigonometric functions. Briefly discuss the importance of understanding the unit circle for precalculus and calculus.
  • Video Viewing (20 mins)
    Watch "Unit Circle Practice A to Z (Degrees & Radians)" by Mario's Math Tutoring. Encourage students to pause the video at each example (A-Z) and attempt to solve it independently before watching the solution. Note: The video content demonstrates practical application of the unit circle.
  • Guided Practice (20 mins)
    Work through selected examples from the video as a class, emphasizing the process of finding reference angles, determining the sign of trigonometric functions in each quadrant, and relating coordinates on the unit circle to trigonometric values. Focus on both degree and radian measures.
  • Independent Practice (20 mins)
    Assign a set of practice problems (similar to those in the video) for students to complete independently. Provide a mix of degree and radian measures and ask students to find sine, cosine, tangent, cosecant, secant, and cotangent values.
  • Wrap-up and Quiz (15 mins)
    Review key concepts and address any remaining questions. Administer the multiple choice and fill in the blank quizzes to assess student understanding.

Interactive Exercises

  • Unit Circle Coordinate Game
    Present an angle in degrees or radians and have students race to identify the coordinates of the corresponding point on the unit circle. This can be done individually or in teams.
  • Trig Value Matching
    Provide a list of angles and a list of trigonometric values (including both sine, cosine, tangent and reciprocal functions). Students must match each angle to its corresponding value.

Discussion Questions

  • How do reference angles simplify the process of finding trigonometric values?
  • How does the unit circle relate to the graphs of trigonometric functions?
  • Explain the relationship between sine, cosine, and tangent and their reciprocal functions (cosecant, secant, and cotangent).

Skills Developed

  • Application of the unit circle.
  • Converting between radians and degrees.
  • Evaluating trigonometric functions.
  • Problem-solving in trigonometry.

Multiple Choice Questions

Question 1:

What is the radian measure of an angle measuring 270 degrees?

Correct Answer: 3π/2

Question 2:

In what quadrant does an angle of 5π/6 radians terminate?

Correct Answer: Quadrant II

Question 3:

What is the value of sin(π/3)?

Correct Answer: √3/2

Question 4:

What is the value of cos(7π/6)?

Correct Answer: -√3/2

Question 5:

What is the value of tan(π/4)?

Correct Answer: 1

Question 6:

What is the value of csc(π/2)?

Correct Answer: 1

Question 7:

What is the value of sec(π)?

Correct Answer: -1

Question 8:

What is the cot(3π/2)?

Correct Answer: 0

Question 9:

The reference angle for 5π/4 is:

Correct Answer: π/4

Question 10:

Which trigonometric function is represented by the x-coordinate on the unit circle?

Correct Answer: cosine

Fill in the Blank Questions

Question 1:

An angle of 315 degrees is equivalent to _____ radians.

Correct Answer: 7π/4

Question 2:

The sine function is the _______ coordinate on the unit circle.

Correct Answer: y

Question 3:

The cosine function is the _______ coordinate on the unit circle.

Correct Answer: x

Question 4:

The tangent of an angle is equal to sine divided by _______.

Correct Answer: cosine

Question 5:

The cosecant is the reciprocal of the _______ function.

Correct Answer: sine

Question 6:

The secant is the reciprocal of the _______ function.

Correct Answer: cosine

Question 7:

The cotangent is the reciprocal of the _______ function.

Correct Answer: tangent

Question 8:

The coordinates of the point on the unit circle corresponding to 0 radians are (_____, _____) .

Correct Answer: 1, 0

Question 9:

The coordinates of the point on the unit circle corresponding to π/2 radians are (_____, _____) .

Correct Answer: 0, 1

Question 10:

The tangent function is undefined at π/2 because the _______ value is zero.

Correct Answer: cosine