graphing functions and finding domain and range.

[Kristen_Opp]

I'm not sure how to graph functions like this:

. . . . . . . . . . . ./ p + 1, 0 < p < 7
. . .c = g(p) =<
. . . . . . . . . . . .\ 5, p > 7

I'm used to working with graphing functions like "y = 3x - 5". How does this new format change the process? I don't really know were to start. Thank you!

 

[wjm11]

c=g(p)=
p+1 if 0 is less than or equal to p less than 7
5 if p is greater than 7

The simple version: Just draw a normal xy-graph, except label it "p" in place of x and "c" in place of y.

Then graph the line c = p + 1, but only part of it -- just the part between the vertical lines p = 0 and p = 7.

Then graph the horizontal line c = 5, but again, only part of it -- just the part to the right of p = 7.

Re the endpoints of the segment and ray you have just drawn: make a solid circle if it's got an "equal to" in the statement; make an open circle if it's only " less than" or " greater than."

Hope that helps.

 

[stapel]

I'm not sure how to graph functions like this:

. . . . . . . . . . . ./ p + 1, 0 < p < 7
. . .c = g(p) =<
. . . . . . . . . . . .\ 5, p > 7

If you prefer, rename:

. . . . . . . . . . . ./ x + 1, 0 < x < 7
. . .y = f(x) =<
. . . . . . . . . . . .\ 5, x > 7

Then graph "y = x + 1" and "y = 5" as usual, but cut the lines off at the indicated enpoints: "x + 1" only "counts" for x between zero and 7, while "5" only "counts" for x-values past 7. The graph is blank before x = 0 (the y-axis).

Eliz.