The Constant Function
A constant function is a function whose range consists of a single element. That is, the output value of the function at any input value in its domain is the same, independent of the input. The mathematical formula for a constant function is just fx=a, where a is a number (which does not depend on x). The graph of a constant function is a horizontal line, that is, a line with slope 0.
Note: it is not necessary for the (single) value of the function, the "a" in the discussion above, to be literally a number, such as 3 or 0 or π. All that matters is that the output, whatever it is, it does not depend on the input variable, x. For example, the function fx=w2 is a constant function with respect to its input variable, x.
Create a constant function
Click or drag on the graph below to move the two blue points.
The line which passes through those points is drawn, and the title of the graph will reflect whether or not the corresponding function is constant.
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