The domain of a function is the collection of independent variables of x, and the range is the collection of dependent variables of y. To find the domain of a function, just plug the x-values into the quadratic formula to get the y-output.
A step by step tutorial, with detailed solutions, on how to find the domain and range of real valued functions is presented. First the definitions of these two concepts are presented.
Domain and Range of a Function. The domain of a function is the set of all possible input values (x-values) for which the function is defined. The range of a function is the set of all possible output values (y-values) the function can produce. The following diagrams show the domain and range of a function.