Course: H.S. Precalculus: Trigonometry



Prove the Pythagorean identity sin^2(x) + cos^2(x) = 1 and use it to find trigonometric ratios, given sin(x), cos(x), or tan(x), and the quadrant of the angle.

I Can Statements Academic Vocabulary

*I can use the Pythagorean Theorem to prove the Pythagorean identities.

*I can use Pythagorean identities to find trigonometric ratios given sine, cosine, or tangent and the quadrant of the angle.

Pythagorean Identity
Trigonometric ratios

Looking Back Looking Ahead

*Use inductive reasoning to explain the Pythagorean Theorem. (MA.8.GM.7)

* Develop geometric proofs, including those involving coordinate geometry, using two-column, paragraph, and flow chart formats. (MA.G.LP.4)

*The concepts and skills in this standard are an integral part of calculus, college-level algebra, and beyond.

Clarifying Examples and Digital Resources
Click here for clarifying examples and digital resources aligned to Indiana standards. These are intended to expand each standard to support instruction in the classroom as evidenced by the Eight Mathematics Teaching Practices put forth by the National Council of Teachers of Mathematics (NCTM).