posted by Brian on .
What is the differnce between a range and domain how can I tell if it is a function or non function. I need a real life example Please help!
Domain: All input values that give a
real output are in the domain.
Y = 35 / (x-2).
All values of x except 2 are within the domain, because 2 gives a denominator of 0 which results in an infinite(undefined) output.
Mathematically: 2 > X > 2.
When a vertical line is drawn through a function, it will intersect at only one point. For example, a vertical line
drawn through the graph of an
x-parabola will intersect at 2 points.
Therefore, it is not a function.
A y-parabola is a function, because it will be intersected at only one point by a vertical line.
The range is all outputs resulting from
inputs within the domain. Therefore, the range of the above function is all
values of y that are greater than negative infinity but less than positive infinitive. So the range includes ALL real numbers.