Visualizing Complex Zeros Of A Cubic Polynomial - Texas Instruments TI-89 Titanium Short User Manual

7. Display the
change
tblStart
Note: Press 8 &.
Display the table in the left side and press D
8.
to highlight
Note: Press 8 '.
Switch to the right side. Press ..., and trace
9.
the graph to show the values of
when .
tc=2
Note: As you move the trace cursor from
to
tc=0.0 tc=3.1
the ball at time
Optional Exercise
Assuming the same initial velocity of 95 feet per second, find the angle
that the ball should be hit to achieve the greatest distance.

Visualizing Complex Zeros of a Cubic Polynomial

This activity describes graphing the complex zeros of a cubic polynomial.
Visualizing Complex Roots
Perform the following steps to expand the cubic polynomial
i i
N N
, find the absolute value of the function, graph the
(x 1)(x )(x+ )
modulus surface, and use the
1. On the Home screen, use the
function to expand the cubic expression
i
N N
(x 1)(x )(x+
2. Copy and paste the last answer to the entry
line and store it in the function
Note: Move the cursor into the history area
to highlight the last answer and press ¸,
to copy it to the entry line.
Activities
dialog box, and
TABLE SETUP
and @
to
0
.
t=2
, you will see the position of
.
tc
Trace
i
and see the first polynomial.
)
to .
tbl 0.1
and
xc yc
tool to explore the modulus surface.
expand( )
.
f(x)
105