EngageNY
Special Triangles and the Unit Circle
Calculate exact trigonometric values using the angles of special right triangles. Beginning with a review of the unit circle and trigonometric functions, class members use their knowledge of special right triangles to find the value of...
Alabama Learning Exchange
Unit Circle: Special Angles—Just Know One
It's all about the patterns! Young scholars learn that the unit circle repeats itself in all four quadrants. Using these patterns, they evaluate the sine, cosine, and tangent of special angles.
Project Maths
The Unit Circle
It's not just any circle—it's the unit circle. The fourth lesson in the series is an introduction to the famous unit circle. While working through a series of activities, young scholars learn the components of the unit circle and how to...
EngageNY
Properties of Trigonometric Functions
Given a value of one trigonometric function, it is easy to determine others. Learners use the periodicity of trigonometric functions to develop properties. After studying the graphs of sine, cosine, and tangent, the lesson connects them...
EngageNY
From Circle-ometry to Trigonometry
Can you use triangles to create a circle? Learners develop the unit circle using right triangle trigonometry. They then use the unit circle to evaluate common sine and cosine values.
EngageNY
Why Call It Tangent?
Discover the relationship between tangent lines and the tangent function. Class members develop the idea of the tangent function using the unit circle. They create tables of values and explore the domain, range, and end behavior of the...
Curated OER
Exercise Set 5.1: Trigonometric Functions of Real Numbers
In this trig functions worksheet, students find the trig values of 46 problems. Students find the trig values of various radian measures. Students use trig properties to prove trig identities.
Curated OER
Right Triangles and Unit Circles
Students evaluate the six trigonometric values of a trig function. In this trigonometry lesson, students use the Unit Circle to find the values of right triangles and their angles. They identify an angle of elevation and depression.
Curated OER
The Unit Circle
Students solve problems using the unit circle. For this precalculus lesson, students identify angles using the properties of the unit circle. They observe the trigonometric graphs and sine, cosine and tangent.
Curated OER
Quadrantal Angles
In this quadrantal angle worksheet, students determine the six trigonometric for each quadrant angle. This one-page worksheet contains 36 problems, with answers printed at the bottom of the page.
Curated OER
Angles in Standard Positions
Young scholars identify positive and negative angles using the Unit Circle. In this pre-calculus lesson, students identify the different angles on a unit circle using the coordinate plane and the four different quadrants as a guide. They...
Curated OER
Unit Circle Lesson Plan
Students identify different locations on a unit circle. For this precalculus lesson, students identify the different trig properties and rewrite the equation of a circle in standard form. They use mnemonic devices to help them remember...
Curated OER
Unit Circle Triangle
Learners find the different ratios of a right triangle. In this geometry lesson, students apply the concept of the Pythagorean theorem as they identify the different angles and parts of a Unit Circle. They find the ratios of sine,...
Curated OER
Introducing Trigonometry
Eleventh graders explore the three basic trigonometric functions. In this trigonometry/Algebra II lesson, 11th graders use GeoGebra and the unit circle to define the ratios of sides is a right triangles as they examine the full domain...
Curated OER
Understanding Fundamental Trigonometric Identities
Students are introduced to the basic trigonometric identities. Using a diagram, they discover why the parts of the unit circle as named as they are and use equations to finalize the Pythagorean trigonometric identities. They also review...
EngageNY
Secant and the Co-Functions
Turn your class upside down as they explore the reciprocal functions. Scholars use the unit circle to develop the definition of the secant and cosecant functions. They analyze the domain, range, and end behavior of each function.
Mathematics Assessment Project
Inscribing and Circumscribing Right Triangles
High schoolers attempt an assessment task requiring them to find the radii of inscribed and circumscribed circles of a right triangle with given dimensions. They then evaluate provided sample responses to consider how to improve their...
Curated OER
Right Triangles and The Unit Circle
Young scholars solve right triangles using trigonometry. In this geometry instructional activity, students use the unit circle to identify different trig values. They identify the six trigonometric identities.
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
Trigonometric Functions of Special Angles
Students explore the concept of the six trigonometric functions, places where the functions can be utilized, and apply these functions to several electrical application problems.
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...
EngageNY
Addition and Subtraction Formulas 2
Knowing the addition formulas allows for the calculations of double and half formulas. The fourth installment of 16 has the class use the addition formula to develop the double angle trigonometric formulas. Using the double formula,...
Illustrative Mathematics
Eratosthenes and the Circumference of the Earth
The class gets to practice being a mathematician in ancient Greece, performing geometric application problems in the way of Eratosthenes. After following the steps of the great mathematicians, they then compare the (surprisingly...
EngageNY
Addition and Subtraction Formulas 1
Show budding mathematicans how to find the sine of pi over 12. The third lesson in a series of 16 introduces the addition and subtraction formulas for trigonometric functions. Class members derive the formulas using the distance formula...