Then you can figure out which is the independent variable and which is the dependent variable: (Independent variable) causes a change in (Dependent Variable) and it isn't possible that (Dependent Variable) could cause a change in (Independent Variable). For example: (Time Spent Studying) causes a change in (Test Score) and it isn't possible that (Test Score) could cause a change in (Time Spent Studying).
Domain and Range. When we look at a function like f(x) = x + 2, we can easily say where the function f(x), in this case, the value along the y-axis, is at any point we choose along the x-axis. We know that at x = 3.4, f(x) = 5.4. The values of x that the function will output a value for is called the domain of f. In the case of f(x) = x + 2, the domain is the entire x-axis, or, formally speaking, all real numbers. The values which f(x) takes on is called the range of f.
The domain of y = sin x is all values of x, since there are no restrictions on the values for x. (Put any number into the sin function in your calculator. From the calculator experiment, and from observing the curve, we can see the range is y betweeen â1 and 1. We could write this as â1 â¤ y â¤ 1.