Texas Instruments TI-86 User Manual

Page 267

Chapter 19: Applications

255

19APPS.DOC TI-86, Chap 19, US English Bob Fedorisko Revised: 02/13/01 2:41 PM Printed: 02/13/01 3:05 PM Page 255 of 18

ᕡ Select

TOL

from the

MEM

menu and set

tol=1

ᕢ On the mode screen, set

Radian

angle mode and

Param

graphing mode.

ᕣ In the equation editor, enter the parametric equations for the power series approximation as

shown. Select

sum

and

seq

from the

LIST

OPS

menu. Select

from the

MATH

PROB

menu.

xt1=t

yt1=sum seq((

1)^(j+1)t^(2j

((2j

1)(2j

1)!),j,1,10,1)

ᕤ In the equation editor, enter the parametric equations as shown to plot the antiderivative of (sin x)àx

and compare it with the plot of the power series approximation. (Select

fnInt

from the

CALC

menu.)

xt2=t

yt2=fnInt((sin w)

w,w,0,t)

ᕥ Select

WIND

from the

GRAPH

menu and set the window variable values as shown.

tMin=

xMin=

yMin=

tMax=15

xMax=15

yMax=3

tStep=0.5

xScl=1

yScl=1

ᕦ Select

FORMT

from the

GRAPH

menu and set

SimulG

format.

ᕧ Select

GRAPH

from the

GRAPH

menu to plot the parametric

equations on the graph screen.

ᕨ In the equation editor, modify

yt1

to compute the first 16 terms of

the power series by changing

. Plot the equations again.

In this example, the window variable

tStep

controls the plotting

speed. Select

WIND

from the

GRAPH

menu and set

tStep=1

and

observe the difference in plotting speed and curve smoothness.

If necessary, select ALL

from the equation editor
menu to deselect all
functions. Also, turn off all
stat plots.

This example is set up in
Param

mode, which allows

you to control the solution
with tStep and increase
plotting speed.

To clear the menus from the
graph screen, press