Unit Circle and Trigonometric Functions

Lesson 2

Math

Unit 6

11th Grade

Lesson 2 of 14

Objective


Sketch cosine graphs to model contextual situations and identify features of cosine graphs.

Common Core Standards


Core Standards

  • F.IF.B.4 — For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship. Key features include: intercepts; intervals where the function is increasing, decreasing, positive, or negative; relative maximums and minimums; symmetries; end behavior; and periodicity. Modeling is best interpreted not as a collection of isolated topics but in relation to other standards. Making mathematical models is a Standard for Mathematical Practice, and specific modeling standards appear throughout the high school standards indicated by a star symbol (★). The star symbol sometimes appears on the heading for a group of standards; in that case, it should be understood to apply to all standards in that group.
  • F.IF.C.7.E — Graph exponential and logarithmic functions, showing intercepts and end behavior, and trigonometric functions, showing period, midline, and amplitude.
  • F.TF.B.5 — Choose trigonometric functions to model periodic phenomena with specified amplitude, frequency, and midline. Modeling is best interpreted not as a collection of isolated topics but in relation to other standards. Making mathematical models is a Standard for Mathematical Practice, and specific modeling standards appear throughout the high school standards indicated by a star symbol (★). The star symbol sometimes appears on the heading for a group of standards; in that case, it should be understood to apply to all standards in that group.

Foundational Standards

  • G.SRT.C.6

Criteria for Success


  1. Identify appropriate situations for a sinusoidal model.
  2. Connect cosine functions with the height of a rotating object over time.
  3. Identify midline, phase shift, period, and amplitude of cosine functions.
  4. Sketch a cosine graph to model a contextual situation.
  5. Identify differences between sine and cosine functions.
Fishtank Plus

Unlock features to optimize your prep time, plan engaging lessons, and monitor student progress.

Anchor Problems

25-30 minutes


Problem 1

Graphed above is a sine function, which measures the height of the point. What if, instead, a function measured the horizontal distance from the y-axis? Sketch what that function might look like.

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

Problem 2

Show the first video of Ferris Wheel by Dan Meyer.

What would the graph look like if you graphed horizontal distance rather than vertical distance? At what point on the cosine graph will riders get on and off?

Guiding Questions

Create a free account or sign in to access the Guiding Questions for this Anchor Problem.

References

101Questions Ferris Wheel

Ferris Wheel by Dan Meyer is made available on 101Questions under the CC BY 3.0 license. Accessed Feb. 26, 2018, 10:38 a.m..

Target Task

5-10 minutes


Zeke Memorial Park has two different-sized Ferris wheels, one with a radius of 75 feet and one with a radius of 30 feet. For either wheel, riders board at the 3 o’clock position. Distances are measured from the center of the wheel, and rotations are measured in degrees.

For each of the letters (a)–(d), answer the following questions: 

  • Does the wheel have a 75-foot radius or 30-foot radius? 
  • Is the function sine or cosine? 
  • Label the period, amplitude, and midline of the two sine graphs.

References

EngageNY Mathematics Algebra II > Module 2 > Topic A > Lesson 2Exit Ticket

Algebra II > Module 2 > Topic A > Lesson 2 of the New York State Common Core Mathematics Curriculum from EngageNY and Great Minds. © 2015 Great Minds. Licensed by EngageNY of the New York State Education Department under the CC BY-NC-SA 3.0 US license. Accessed Dec. 2, 2016, 5:15 p.m..

Modified by Fishtank Learning, Inc.

Additional Practice


The following resources include problems and activities aligned to the objective of the lesson that can be used for additional practice or to create your own problem set.

  • Include problems asking about both sine and cosine functions.
  • Include problems connecting graphs and contextual situations.
  • Include problems finding periods of graphs and extrapolating to emphasize periodic behavior.
  • Include problems that measure the x-axis both in time and in degrees.

Next

Find values of specific points on the unit circle using geometry.

Lesson 3
icon/arrow/right/large

Lesson Map

A7CB09C2-D12F-4F55-80DB-37298FF0A765

Topic A: Trigonometric Ratios in Application and on the Unit Circle

Topic B: Graphing Sine, Cosine, and Target

Request a Demo

See all of the features of Fishtank in action and begin the conversation about adoption.

Learn more about Fishtank Learning School Adoption.

Contact Information

School Information

What courses are you interested in?

ELA

Math

Are you interested in onboarding professional learning for your teachers and instructional leaders?

Yes

No

Any other information you would like to provide about your school?

We Handle Materials So You Can Focus on Students

We Handle Materials So You Can Focus on Students

We've got you covered with rigorous, relevant, and adaptable math lesson plans for free