Functions in Algebra 2 are classified into different categories that include quadratic functions, exponential and logarithmic functions, trigonometric functions and linear functions. Some common functions in algebra 2 are quadratic functions, which are represented by function terms such as f(x), which is the sum of two coefficients and a constant. The degree of a quadratic function is typically 2, and it must never be less than this number.

Quadratic functions are typically written as f(x) = ax^2 + bx + c, where a and b are coefficients and c is a constant. A quadratic function typically has either a maximum or a minimum point. A minimum point exists if the graph of the quadratic function (parabola) opens upwards, but if it opens downwards, then the parabola has a maximum point.

If the graph of a quadratic function crosses the x-axis twice, then it is said to have two x-intercepts, which are normally used to find a solution for the corresponding quadratic equation. Lamar University explains that a function is an equation for which a single x can be input into the equation to generate a single y. This means that functions are just sets of ordered pairs of components that are related.