Mathalicious: The Sound of Silence
Mathalicious

In this lesson, students use transformations of trigonometric functions to explore how sound waves can interfere with one another, and how noise-canceling headphones use incoming sounds to figure out how to produce that sweet, sweet silence.

Khan Academy: Pre-Calculus
Khan Academy

TheĀ Precalculus course, often taught in the 12th grade, covers Polynomials; Complex Numbers; Composite Functions; Trigonometric Functions; Vectors; Series, Conic Sections, Probability and Combinatorics.