Recall that a function can be thought of as a machine which takes an input in (say x) and then depending on what that input is, it returns an output (say y) by some predefined rule (say f). The graph ...

Charles Blackorby, William Schworm, The Existence of Input and Output Aggregates in Aggregate Production Functions, Econometrica, Vol. 56, No. 3 (May, 1988), pp. 613-643 ...

Let us keep linear and once the right input amplitude is found, i.e., a signal of comfortable amplitude is observed on the oscilloscope screen, the frequency is varied step by step while output ...