Domain is all of the possible X-values.
Range is all of the possible Y-Values
Functions are equations where the y value depends on what the x value is. functions are as simple as y=x or y=2x+6. Based on what restrictions are set on the function all the the possible x values that can go into the function is the domain while all of the possible y values that can go into the function is the range.
When notating the domain and range, if the line ends at a certain point and the end point is a closed dot then the the notation for it is [ or ]
If the end point is an open dot, the end point is not a definite point, or if the line goes to infinity then the notation is ( or ) Whenever the graph goes to infinity it is always notated with (∞ or ∞)
For example, if the graph was y=x
If the end point is an open dot, the end point is not a definite point, or if the line goes to infinity then the notation is ( or ) Whenever the graph goes to infinity it is always notated with (∞ or ∞)
For example, if the graph was y=x
For the domain you look on the x axis for all of the points where there is a possible value of x. With this graph it is (∞,∞)
Then, for range you look on the Y-axis and find all of the possible y values. With this graph it is also (∞,∞)
Then, for range you look on the Y-axis and find all of the possible y values. With this graph it is also (∞,∞)
If the points from a graph were (2, –3), (4, 6), (3, –1), (6, 6), (2, 3) then, the domain comes from the lowest and highest first numbers because that is the x-value which makes the domain [2,6] with brackets because it from a definite point. For the range you get the lowest and highest numbers from the second number because that is the y value. That makes the range [-3,6] and again it is with brackets because it is a definite point.