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Instructional Video10:36
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Flipped Math

Inverse Trig Ratios

For Students 9th - 12th Standards
Put trigonometric ratios into inverse. Scholars learn how to find an unknown angle in a right triangle by using inverse trigonometric ratios. The pupils understand how the inverses undo a trigonometric ratio to provide the angle measure....
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Instructional Video20:08
2
2
Flipped Math

Trig Ratios

For Students 9th - 12th Standards
Take ratios of sides to a new level. Pupils learn the definitions of the three basic trigonometric ratios in right triangles. Using the definitions, scholars find missing lengths in right triangles, based on a known angle. Individuals...
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Lesson Plan
Curated OER

Basic Trigonometric Ratios

For Teachers 11th - 12th
In this trigonometric ratio worksheet, students determine the length of a side of a right triangle, or the measurement of angles using trigonometric ratios. This one-page worksheet contains 24 problems. Answers are provided at the bottom...
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Lesson Plan
EngageNY

Incredibly Useful Ratios

For Students 9th - 10th Standards
Start the exploration of trigonometry off right! Pupils build on their understanding of similarity in this lesson that introduces the three trigonometric ratios. They first learn to identify opposite and adjacent sides before exploring...
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Interactive
CK-12 Foundation

Basic Trigonometric Functions: Ladder Length

For Students 9th - 12th Standards
Climb the ladder to trigonometry. The interactive introduces trigonometric ratios and finding lengths of sides of right triangles created by a ladder and a building. Learners use the interactive to create triangles by moving the top of...
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Lesson Plan
West Contra Costa Unified School District

Introduction to Trigonometric Functions

For Teachers 9th - 12th
Scholars first learn the definitions of the sine ratio, the cosine ratio, and the tangent ratio. After mastering these definitions, they use the new information to solve triangles.
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Lesson Plan
EngageNY

Trigonometry and the Pythagorean Theorem

For Students 9th - 11th Standards
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...
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Interactive
CK-12 Foundation

Reciprocal Identities

For Students 10th - 12th Standards
Get a better understanding of the trigonometric functions by taking a look at the flip side. Pupils create angles within a unit circle and compare the values of the standard trigonometric functions to their reciprocal functions. The...
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Lesson Plan
Curated OER

How are Trig Ratios Used to Measure Triangle Sides

For Teachers 8th - 11th
Students identify the ratios of trig identities. In this geometry lesson, students solve the missing sides and angles of triangles using trig ratios. They relate the graphs and waves to real life scenarios.
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Lesson Plan
EngageNY

The Definition of Sine, Cosine, and Tangent

For Students 9th - 10th Standards
Introduce your classes to a new world of mathematics. Pupils learn to call trigonometric ratios by their given names: sine, cosine, and tangent. They find ratios and use known ratios to discover missing sides of similar triangles. 
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Lesson Plan
Project Maths

Introduction to Trigonometry

For Teachers 9th - 12th Standards
The topic of trigonometric ratios is often covered with loads of rote memorization baked into the activity. This activity set, however, leans more on using similar triangles and discovery learning to help young geometers develop a deeper...
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Lesson Plan
EngageNY

Sine and Cosine of Complementary Angles and Special Angles

For Students 9th - 10th Standards
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...
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Lesson Plan
Curated OER

The Tangent Ratio

For Teachers 8th - 11th
Learners calculate the tangent ratio given a right triangle. In this trigonometry lesson, students use a right triangle and the Pythagorean Theorem to solve problems.
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Interactive
CK-12 Foundation

Double Angle Identities: Ferris Wheel

For Students 10th - 12th
Use a Ferris wheel to soar to new heights of understanding on double angle identities. Here is an interactive that applies an example of a Ferris wheel to show how doubling the angle does not double the value of a trigonometric ratio....
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Interactive
CK-12 Foundation

Fundamental Trigonometric Identities: Tangent Identity

For Students 10th - 12th
An identity that thieves can't steal  the tangent identity. Scholars manipulate ratios to investigate the tangent ratio and connect it to the sine and cosine ratios. An interactive that uses color coding helps with this task.
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Lesson Plan
Curated OER

Trigonometric Ratios

For Teachers 10th - 12th
Young scholars measure and analyze angles. In this trigonometry lesson, students measure angles and distances use non-traditional techniques. They identify the different ratios of sine, cosine and tangent.
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Lesson Plan
Virginia Department of Education

Special Right Triangles and Right Triangle Trigonometry

For Teachers 9th - 11th Standards
Right triangles are so special! Use special right triangles to discover the trigonometric ratios. Pairs construct special right triangles and find the values of the ratios of the sides. In the process, they discover the ratios stay the...
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Lesson Plan
EngageNY

Unknown Angles

For Students 9th - 10th Standards
How do you solve an equation like trigonometry? Learners apply their understanding of trigonometric ratios to find unknown angles in right triangles. They learn the meaning of arcsine, arccosine, and arctangent. Problems include basic...
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Lesson Plan
Alabama Learning Exchange

"I Saw the Sine"

For Teachers 9th - 12th Standards
Discover trigonometric ratios that complement each other. Using two videos, the lesson introduces the trigonometric ratios. The class discovers the relationship between the sine and cosine of complementary angles.
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Interactive
CK-12 Foundation

Pythagorean Theorem for Solving Right Triangles: Solving the Triangle

For Students 9th - 12th Standards
Observe the change in the trigonometric ratios as angles vary. An interactive provides the values of trigonometric ratios for both acute angles in a right triangle. Pupils create a right triangle to match given criteria and find the...
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Lesson Plan
Curated OER

Introducing Trig

For Teachers 5th
Fifth graders explore the importance of triangles in the real world. They find the unknown side of a right triangle using a scale drawing. Students use Pythagoras' Theorem and other appropriate ratios.
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Lesson Plan
Curated OER

Investigating Trigonometric Ratios Through Similar Right Triangles

For Teachers 9th - 10th
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.
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Interactive
CK-12 Foundation

Secant, Cosecant, and Cotangent Functions: Hold the Ladder!

For Students 9th - 12th Standards
Determine the length of a falling ladder. Pupils use an interactive to find the angle a ladder makes with the floor after it falls to answer questions. The scholars use the triangle formed in the interactive to determine values of...
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Lesson Plan
Curated OER

Amazing Consistent Ratios

For Teachers 7th - 9th
Students derive the six trigonometric identities. In this trigonometry lesson, students find the ratios of sine, cosine and tangent using the right triangle. They use properties of the Pythagorean Theorem to find the trig identities.