Proving Trigonometric Identities

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...

The Pythagorean Theorem makes an appearance yet again in this lesson plan on polynomial identities. Learners prove a method for finding Pythagorean triples by applying the difference of squares identity. 

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...

In this trigonometric identities learning exercise, students solve 16 multi-part short answer problems. Students use the quotient identity and Pythagorean identity to simplify trigonometric expressions. Students factor trigonometric...

Students solve trigonometric equations. In this precalculus lesson, students prove trigonometric identities using the Pythagorean Theorem. They apply the addition formulas for sine and cosine to prove different identities.

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.

The Hopewell people of the central Ohio Valley used right triangles in the construction of earthworks. Pupils use the Pythagorean Theorem to determine missing dimensions of right triangles used by the Hopewell people. The assessment task...

Middle and high schoolers explore the concept of proving the Pythagorean Theorem. They research proofs of the Pythagorean Theorem. Pupils create posters of proofs, and research Greek mathematicians.

Most adults remember learning about the Pythagorean theorem, but they don't all remember how to use it. The emphasis here is on developing an intuitive understanding of how and when to use the theorem. Young mathematicians explore...

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.