Household Expenditure -- Variables, a Short Taxonomy -- Sets and Functions -- Market Equilibrium Model -- Rates of Change and the Derivative -- Optimal Level of Output and Long Run Price -- Nonlinear Models -- Additional Topics in Perfect and Imperfect Competition -- Logarithmic and Exponential Functions -- Production Function, Least-Cost Combination of Resources, and Profit Maximizing Level of Output -- Economics Dynamics -- Mathematics of Interest Rates and Finance -- Matrices and Their Applications.