EngageNY
Proving Trigonometric Identities
Young mathematicians first learn the basics of proving trigonometric identities. They then practice this skill on several examples.
EngageNY
Basic Trigonometric Identities from Graphs
Have young mathematicians create new identities! They explore the even/odd, cofunction, and periodicity identities through an analysis of tables and graph. Next, learners discover the relationships while strengthening their understanding...
Project Maths
Trigonometric Functions
From a circle to a cycle! The final lesson of a five-part series challenges learners to use points from the unit circle to plot a repeating pattern. The repeating patterns become the graphs of the trigonometric functions. Scholars also...
Curated OER
Does Your Field Measure Up
Students measure angles using a plane table kit. In this geometry instructional activity, students use trigonometric identities to find the values of the length of a football field.
EngageNY
What Is a Trigonometric Identity?
Protect yourself from identity theft! Establishing a strong understanding of the Pythagorean identity allows learners to prove that sine^2x + cos^2x = 1. They then use the identity to find sine or cosine ratios given the other.
Curated OER
Proof of Identity
Learners explore trigonometric identities. In this Algebra II lesson, students use graphing to verify the reciprocal identities. Using Cabri Jr, learners investigate the Pythagorean trigonometric identities and the geometric c proofs...
Curated OER
Graphs of the OTHER Trig Functions
Students graph trigonometric functions. In this precalculus lesson, students identify the properties of secant ,cosecant and cotangent. They use the unit circle as their formula to graph and analyze these functions.
EngageNY
Solving Problems Using Sine and Cosine
Concepts are only valuable if they are applicable. An informative resource uses concepts developed in lessons 26 and 27 in a 36-part series. Scholars write equations and solve for missing side lengths for given right triangles. When...
EngageNY
Trigonometric Identity Proofs
Proving a trig identity might just be easier than proving your own identity at the airport. Learners first investigate a table of values to determine and prove the addition formulas for sine and cosine. They then use this result to...
EngageNY
Extending the Domain of Sine and Cosine to All Real Numbers
Round and round we go! Pupils use reference angles to evaluate common sine and cosine values of angles greater than 360 degrees. Once they have mastered the reference angle, learners repeat the process with negative angles.
Curated OER
Exploring Trigonometric Ratios
Students identify the ratios of trig functions. In this trigonometry lesson, students construct triangles and use it to derive the values of sine, cosine and tangent. They use Cabri software to create the visual of the identities.
K20 LEARN
Round and Round We Go
Connect the dots on trigonometry with K'nex. Scholars use a K'nex model of a Ferris wheel to collect data points to plot on a height versus time graph. They'll then consider what type of function best models the data in the graph—and...
Mathematics Vision Project
Similarity and Right Triangle Trigonometry
Starting with similar triangles and dilation factors, this unit quickly and thoroughly progresses into the world of right triangle features and trigonometric relationships. Presented in easy-to-attack modules with copious application...
Curated OER
Geometry Exploration Basic Trig Functions
Tenth graders solve for missing sides on a triangle using the Pythagorean Theorem. In this geometry lesson, 10th graders are introduced to basic trigonometry functions as they solve problems of right triangles. They discuss the formulas...
Mathematics Vision Project
Module 6: Trigonometric Functions
Create trigonometric functions from circles. The first lesson of the module begins by finding coordinates along a circular path created by a Ferris Wheel. As the lessons progress, pupils graph trigonometric functions and relate them to...
EngageNY
Using Trigonometry to Find Side Lengths of an Acute Triangle
Not all triangles are right! Pupils learn to tackle non-right triangles using the Law of Sines and Law of Cosines. After using the two laws, they then apply them to word problems.
EngageNY
Sine and Cosine of Complementary Angles and Special Angles
Building trigonometric basics here will last a mathematical lifetime. Learners expand on the previous lesson in a 36-part series by examining relationships between the sine and cosine of complementary angles. They also review the ratios...
Curated OER
Woody Sine
Students explore the concept of sine. In this sine lesson, students create a sine graph from tooth picks. Students create a unit circle with tooth pick length radius. Students then take the tooth picks from the unit circle and put them...
Alabama Learning Exchange
Technology for Displaying Trigonometric Graph Behavior: Sine and Cosine
Students explore the concept of sine and cosine. In this sine and cosine lesson, students work in groups to graph sine and cosine functions. Students examine how coefficients in various parts of each parent function shift the graph. ...
Curated OER
Trig is SOH Easy!
Students derive the six trigonometric identities. In this trigonometry lesson, students review the parts of a right triangle and use the Pythagorean theorem as a guide to find the trig identities. They find sine, cosine and tangent ratios.
Curated OER
Investigating Trigonometric Ratios Through Similar Right Triangles
Students identify similar and congruent right triangles. In this geometry lesson, students use trigonometric ratios to identify missing sides and angles of a triangle. They differentiate similar and congruent triangles.
EngageNY
Trigonometry and the Pythagorean Theorem
Ancient Egyptians sure knew their trigonometry! Pupils learn how the pyramid architects applied right triangle trigonometry. When comparing the Pythagorean theorem to the trigonometric ratios, they learn an important connection that...
Curated OER
Trigonometric Identities
Students calculate the six trigonometric identities. In this algebra lesson plan, students verify other identities using the basic trigonometric identities of sine, cosine and tangent. They complete a worksheet with hints and then are...
Texas Instruments
What's the Trig?
Learners determine the trigonometric relationships within a triangle as they construct a right triangle on the Ti-89. They find the sine, cosine, and tangent of various angles of their triangle construction.