Every page in this folder names an idea you first met messily — at the boards, in a visibly random group, marker in hand. That order is deliberate: the wrestling builds the understanding, and these pages consolidate it, written for your future forgetful self. Read them after the exploration, never instead of it.

Unit 1 — Functions and transformations

Unit 2 — Exponential functions

Unit 3 — Trigonometric functions

Unit 4 — Discrete functions and your financial future

Most pages end by pointing at the practice set that turns the idea into a reflex, and at the curriculum expectations the page serves — so you can always see where you are and why we are here.