Lesson: The Cosine Ratio Mathematics

Students will be able to

• use right triangles to find cosine ratios,
• use special right triangles to find the cosine ratios for , , and ,
• use the cosine ratio to find missing lengths in right triangles,
• use the inverse cosine ratio to find missing angle measures in right triangles,
• solve more complex problems, such as using the cosine ratio or inverse cosine ratio in combination with the Pythagorean theorem, simple 2D shape properties, or coordinate geometry.