Question

What is a real life example of a non-function?

Answer 1

killing 2 birds with one stone ....

Answer 2

Suppose x^2 +y^2 =25. (This is the circle with center at the origin and radius 5.) What is y when x = 3? Clearly y can take on two values, +/- 4, so this is not a function.

Here is something to think about in "real life":

Suppose I ask each student in a class to write down his or her social security number. That has a definitive answer. For each student there is only one social security number. This is an example of a function.

Now suppose I ask each student to write down his or her phone number. Chances are that there is more than one response to this. A student may have a home phone, a cell phone, possibly a work phone, ... There is no definitive output for each student. This is not a function.

Answer 3

any action that results in more than one outcome so that you simply cannot predict with any degree of accuracy the cause and effect between them

Answer 4

Thankyou so much both answers were a great help :)