Texas Instruments TI-86 ユーザーズマニュアル
Chapter 3: Math, Calculus, and Test Operations
55
03MATH.DOC TI-86, Chap 3, US English Bob Fedorisko Revised: 02/13/01 2:19 PM Printed: 02/13/01 3:00 PM Page 55 of 10
03MATH.DOC TI-86, Chap 3, US English Bob Fedorisko Revised: 02/13/01 2:19 PM Printed: 02/13/01 3:00 PM Page 55 of 10
The built-in variable
d
defines the step size in calculating
nDer(
(in
dxNDer
differentiation
mode only) and
arc(
. The built-in variable
tol
defines the tolerance in calculating
fnInt(
,
fMin(
,
fMax(
, and
arc(
. The value of each must be >0. These factors affect the accuracy of the
calculations. As
d
becomes smaller, the approximation typically is more accurate. For
example,
nDer(A^3,A,5)
returns
75.0001
if
d
=.01
, but returns
75
if
d
=.0001
(Appendix).
The function integral error value is stored to the variable
fnIntErr
(Appendix).
For
arc(
and
fnInt(
while
dxDer1
mode is set, these functions are not valid in expression:
evalF(
,
der1(
,
der2(
,
fMin(
,
fMax(
,
nDer(
,
seq(
, and any equation variable, such as
y1
.
You can approximate the fourth derivative at the current value of x with this formula:
nDer(nDer(der2(x^4,x),x),x)
.
The TEST (Relational) Menu
- ˜
= =
<
>
‚
4
ƒ
valueA
==
valueB
(equal to) Returns
1
if valueA is equal to valueB; returns
0
if not equal; valueA and
valueB
can be real or complex numbers, lists, vectors, matrices, or strings
valueA
<
valueB
(less than) Returns
1
if valueA is less than valueB; returns
0
if valueA is not less than
valueB
; valueA and valueB must be real numbers or lists
valueA
>
valueB
(greater than) Returns
1
if valueA is greater than valueB; returns
0
if valueA is not
greater than valueB; valueA and valueB must be real numbers or lists
valueA
valueB (less than or equal to) Returns
1
if valueA is less than or equal to valueB; returns
0
if valueA
is not less than or equal to valueB; valueA and valueB must be real numbers or lists
Relational functions are valid
for two lists of the same
length. When
for two lists of the same
length. When
valueA
and
valueB
are lists, a list of
results calculated element by
element is returned.
element is returned.