Solving A System Of Nonlinear Equations - Texas Instruments TI-82 STATS Manual Book

Solving a System of Nonlinear Equations

Problem
Procedure
17–6 Applications
Using a graph, solve the equation X
another way, solve the system of two equations and two
3
unknowns: Y = X N2X and Y = 2cos(X). Use
control the decimal places displayed on the graph.
1. Press z. Select the default mode settings. Press o. Turn
off all functions and stat plots. Enter the functions.
2. Press q
to select
4
two solutions may exist (points where the two functions
appear to intersect).
3. Press q ~
4
menu. Set
MEMORY
4. Press q
to select
2
move the free-moving cursor onto the apparent intersection
of the functions on the right side of the display. As you move
the cursor, notice that the
place.
5. Press Í to zoom in. Move the cursor over the
intersection. As you move the cursor, notice that now the
and values have two decimal places.
Y
6. Press Í to zoom in again. Move the free-moving cursor
onto a point exactly on the intersection. Notice the number
of decimal places.
7. Press y [
CALC
select the first curve and Í to select the second curve.
To guess, move the trace cursor near the intersection. Press
Í. What are the coordinates of the intersection point?
8. Press q
to select
4
graph.
9. Press q. Select
to explore the apparent function intersection on the left side
of the display.
3
N 2X = 2cos(X). Stated
. The display shows that
4:ZDecimal
to select
4:SetFactors
and
XFact=10
. Use |, ~, }, and † to
2:Zoom In
and values have one decimal
X Y
] to select
5 5:intersect
4:ZDecimal
and repeat steps 4 through 8
2:Zoom In
factors to
ZOOM
from the
ZOOM
.
YFact=10
. Press Í to
to redisplay the original
X