Texas Instruments TI-89 Titanium User Manual page 391

• Because of possible long evaluation times, you first may want to experiment with
your 3D equation by using Style=WIRE FRAME. The evaluation time is much
shorter. Then, after you're sure you have the correct Window variable values,
display the Graph Formats dialog box and set Style=CONTOUR LEVELS or WIRE
AND CONTOUR.
8 Í
Example: Contours of a Complex Modulus Surface
The complex modulus surface given by
of any polynomial
Example
In this example, let f(x)=x
can express the complex surface equation as z(x,y)=abs((x+yi)
1. Use 3 to set
2. Press 8 #, and define the equation:
z1(x,y)=abs((x+yù
3. Press 8 $, and set the Window
variables as shown.
3D Graphing
.
y=f(x)
3
+1. By substituting the general complex form x+y
.
Graph=3D
)^3+1)
i
z(a,b) = abs(f(a+bi))
shows all the complex zeros
for x, you
i
3
+1).
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