Texas Instruments TI-89 Titanium User Manual

3D Graphing 390
Notes:
• For more accurate estimates, increase the xgrid and ygrid Window variables.
However, this increases the graph evaluation time.
• When you animate the graph, the screen changes to normal view. Use p to toggle
between normal and expanded views.
Implicit Plots
An implicit plot is used primarily as a way to graph 2D implicit forms that cannot be
graphed in function graphing mode. Technically, an implicit plot is a 3D contour plot with
a single contour drawn for
z=0 only.
Explicit and Implicit Forms
In 2D function graphing mode, equations have
an explicit form
y=f(x), where y is unique for
each value of x.
Many equations, however, have an implicit
form
f(x,y)=g(x,y), where you cannot explicitly
solve for y in terms of x or for x in terms of y.
y is not unique for
each x, so you cannot
graph this in function
graphing mode.

Texas Instruments TI-89 Titanium Specifications

General

Display Type	LCD
Display Resolution	160 x 100 pixels
CPU	Motorola 68000
CPU Speed	16 MHz
RAM	256 KB
Flash ROM	2.7 MB
Programming Language	TI-BASIC, Assembly
Power Source	4 AAA batteries
Connectivity	I/O port
Dimensions	7.5 x 3.5 x 1 inches