A function relates one set of inputs (independent variables) to another set of outputs (dependent variables). In this case, z(x) is an example of such a function.
An independent variable in calculus refers to a quantity that can be changed or controlled by someone conducting an experiment or solving an equation. Here, x serves as our independent variable.
Dependent Variable: A dependent variable in calculus refers to a quantity that depends on the independent variable. In this case, z(x) is our dependent variable, as it depends on the value of x.