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curves intercept at two points. Move the cursor near the left intercept
point and press
@)@FCN!
@ISECT
, to get I-SECT: (-0.6834…,0.21585).
Press
L
to recover the menu.
•
To leave the FCN environment, press
@)PICT
(or
L
)PICT
).
•
Press
@CANCL
to return to the PLOT WINDOW environment. Then,
press
L
@@@OK@@@
to return to normal calculator display.
Note
: the stack will show all the graph operations performed, properly
identified.
•
Enter the PLOT environment by pressing, simultaneously if in RPN
mode,
„ñ
. Notice that the highlighted field in the PLOT
environment now contains the derivative of Y1(X). Press
L
@@@OK@@@
to
return to return to normal calculator display.
•
Press
‚
@@EQ@@
to check the contents of EQ. You will notice that it
contains a list instead of a single expression. The list has as elements
an expression for the derivative of Y1(X) and Y1(X) itself.
Originally, EQ contained only Y1(x). After we pressed
@@F
'
@@
in the
@)FCN@
environment, the calculator automatically added the derivative of
Y1(x) to the list of equations in EQ.
Saving a graph for future use
If you want to save your graph to a variable, get into the PICTURE
environment by pressing
š
. Then, press
@EDIT
LL
@PICT
. This
captures the current picture into a graphics object. To return to the stack,
press
@)PICT
@CANCL
.
In level 1 of the stack you will see a graphics object described as
Graphic
131
×
64
. This can be stored into a variable name, say, PIC1.
To display your figure again, recall the contents of variable PIC1 to the stack.
The stack will show the line:
Graphic 131
×
64
. To see the graph, enter
the PICTURE environment, by pressing
š
.
Clear the current picture,
@EDIT
L
@ERASE
.
