The graphic calculator!
ON: (on) duh
Write your equation for the graph: (y=)
Once the equation is set, you will see your equation by pressing (trace)
ZoomBox = Zoom to certain area that you selected.
You'll see a blinking cursor, set it to where your zoom's upper-left corner is. (Enter) Then set it to where the zoom's lower-right corner is. (Enter) it would zoom to your desired zoom
Alternatively, you can set the max of X and Y axes by pressing (window) and setting to how far of each axis you want to see.
Calculate on the graph: (2nd)(trace)
Value: of Y when X is ____
Maximum: the maximum turning point for a ∩ shaped curve
Minimum: the minimum turning point for a ∪ shaped curve
For use of both the above, find the left and right bounds, where you think the maxi/mini is. Then make a guess on where the maxi/mini point is. The calc will help find it for you afterwards.
:D :D :D :D