Explain how the vertical line test is used to detect functions.

Step-by-step solution Step 1 of 1 Vertical line test is used to detect function, According to the vertical line test: A graph represents a function if and only if it passes the vertical line test: Every vertical line intersect the graph at most once. A graph that fails this test does not represent a function. The vertical test tells us that if the vertical line intersects the graph in more than one point, then for one value of x we have more than o ne value of f (x). In this case the graph does not represent the function, because one of definition of function is that for one value of x we have one and only one value of f (x). For example: Here first graph shows a function but second is not.