Question

Are this functions yes or no how can I tell if it is ?

Answer 1

Yes they all are functions

Functions should include

• Two variables (Here they are x and f(x))
• Must have domain and range.
• Function must return a new value as output when any input is given .

Answer 2

yes they are all functions

Explanation:

Despite f(x) being the classic way to write a function,

a function has:

• an input (domain)
• a relationship (maps to)
• an output (range)

A function relates each element of a set with exactly one element of another (possibly the same) set.

One-to-one and many-to-one are functions, but one-to-many is not a function.

You can also carry out the Vertical Line Test on a graph. If the vertical line only crosses the curve once, it is a function. If it crosses more than once it is still a valid curve, but is not a function.