The document discusses key concepts related to the cosine function including its graph, formula, domain and range, quadrants and period, intervals of increasing and decreasing values, zeros of the function, and points of maxima and minima. It defines the dependent variable Y and independent variable X. It identifies the domain as all real numbers and the range as [-1,1]. It outlines the four quadrants and states the period is from 0 to 2π. It notes the intervals where the cosine function is increasing and decreasing, and identifies the x-values where the function is zero as well as the points of maxima and minima.