This is a junior/senior level mathematics course, intended for students who have completed two years of algebra and one year of geometry. Trig/Precalc is a journey through different mathematical topics and concepts, expanding on previous algebraic and geometric knowledge. The goal of this course is to explore functions, relations, the area of trigonometry, advanced graphing, and beyond.
Larson, Hostetler, Edwards, Precalculus With Limits: A Graphing Approach
edition, 2001 (Link