# Slope Fields - HP F2226A - 48GII Graphic Calculator User Manual

Graphing calculator.

Press LL@) P ICT to leave the EDIT environment.

## Slope fields

Slope fields are used to visualize the solutions to a differential equation of the
form y' = f(x,y). Basically, what is presented in the plot are segments
tangential to the solution curves, since y' = dy/dx, evaluated at any point (x,y),
represents the slope of the tangent line at point (x,y).
For example, to visualize the solution to the differential equation y' = f(x,y) =
x+y, use the following:
Press „ô, simultaneously if in RPN mode, to access to the PLOT
SETUP window.
Change
to
TYPE
Slopefield.
Press ˜ and type 'X+Y' @@@OK@@@.
Make sure that 'X' is selected as the
variables.
Press „ò, simultaneously if in RPN mode, to access the PLOT
WINDOW screen.
Change the plot window ranges to read:
5
Press @ERASE @DRAW to draw the slope field plot.
@LABEL @MENU to see the plot unencumbered by the menu and with
identifying labels.
Press LL@) P ICT to leave the EDIT environment.
and 'Y' as the
Indep:
X-Left:-5, X-Right:5, Y-Near:-5, Y-Far:
Press @EDIT L
Depnd:
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