Some useful PLOT operations for FUNCTION plots
In order to discuss these PLOT options, we'll modify the function to force it to
have some real roots (Since the current curve is totally contained above the x
axis, it has no real roots.) Press ‚@@@Y1@@ to list the contents of the function Y1
on the stack: <<
Next, store the modified expression into variable y by using „@@@Y1@@ if in RPN
mode, or „îK @@@Y1@@ in ALG mode.
The function to be plotted is now,
Enter the PLOT WINDOW environment by entering „ò(press them
simultaneously if in RPN mode.)
˜@AUTO to generate the V-VIEW. To plot the graph, press @ERASE @DRAW
Once the graph is plotted, press @) @ FCN! to access the function menu.
With this menu you can obtain additional information about the plot
such as intersects with the x-axis, roots, slopes of the tangent line, area
under the curve, etc.
For example, to find the root on the left side of the curve, move the
cursor near that point, and press @ROOT. You will get the result: ROOT: -
1.6635.... Press L to recover the menu.
ROOT in the current plot:
If you move the cursor towards the right-hand side of the curve, by
pressing the right-arrow key (™), and press @ROOT, the result now is
X 'EXP(-X^2/2)/ (2* ) ' >>. To edit this expression use:
Keep the range of –4 to 4 for H-VIEW, press
Launches the line editor
Moves cursor to the end of the line
Modifies the expression
Returns to calculator display
Here is the result of