O: Operations on Numbers and Expressions
O1. Real numbers
O2. Complex numbers
O3. Algebraic expressions
E: Equations and Inequalities
E1. Linear equations and inequalities
E2. Nonlinear equations and inequalities
P: Polynomial and Rational Functions
P1. Quadratic functions
P2. Higher-order polynomial and rational functions
X: Exponential functions
X1. Exponential functions
F: Function Operations and Inverses
F1. Function operations and composition
F2. Inverse functions
F3. Piecewise functions