Calculator User Manual
Appendix A: Functions and Instructions   503
8992APPA.DOC TI-89 / TI-92 Plus: Appendix A (US English) Susan Gullord Revised: 02/23/01 1:48 PM Printed: 02/23/01 2:21 PM Page 503 of 132
SinReg
MATH/Statistics/Regressions menu
SinReg 
list1
, 
list2 
[
, 
[
iterations
]
, 
[ 
period
] [
, 
list3
, 
list4
]
]
Calculates the sinusoidal regression and
updates all the system statistics variables.
All the lists must have equal dimensions
except for 
list4
.
list1
 represents xlist.
list2
 represents ylist.
list3 
represents category codes.
list4 
represents category include list.
iterations
 specifies the maximum number of
times (1 through 16) a solution will be
attempted. If omitted, 8 is used. Typically,
larger values result in better accuracy but
longer execution times, and vice versa.
period
 specifies an estimated period. If
omitted, the difference between values in
list1
 should be equal and in sequential order.
If you specify 
period
, the differences between
x values can be unequal.
Note: 
list1
 through 
list3
 must be a variable
name or c1–c99 (columns in the last data
variable shown in the Data/Matrix Editor).
list4
 does not have to be a variable name and
cannot be c1–c99.
The output of 
SinReg
 is always in radians,
regardless of the angle mode setting.
In function graphing mode:
seq(x,x,1,361,30)
!
L1 
¸
{1
 3
1
 6
1
 …
}
{
5.5,8,
11
,
1
3.5,
1
6.5,
1
9,
1
9.5,
1
7,
1
4.5,
1
2.5,8.5,6.5,5.5
}
!
L2 
¸
{
5.5 8 
11
 …
}
SinReg L
1
,L2 
¸
Done
S
h
owStat 
¸
¸
regeq(x)
!
y1(x) 
¸
Done
NewPlot 1,1,L1,L2 
¸
Done
¥%
„
9
solve()
MATH/Algebra menu
solve(
equation
, 
var
) 
⇒
Boolean expression
solve(
inequality
, 
var
) 
⇒
Boolean expression
Returns candidate real solutions of an equation
or an inequality for 
var
. The goal is to return
candidates for all solutions. However, there
might be equations or inequalities for which the
number of solutions is infinite.
solve(a
ù
x^2+b
ù
x+c=0,x)
¸
x
= 
b
ñ
-4
ø
a
ø
c-b
2
ø
a
or x
= 
ë
(
b
ñ
-4
ø
a
ø
c+b)
2
ø
a
Solution candidates might not be real finite
solutions for some combinations of values for
undefined variables.
ans(1)
|
 a=1 and b=1 and c=1
¸
Error: Non-real result
For the AUTO
 setting of the 
Exact/Approx
 mode,
the goal is to produce exact solutions when
they are concise, and supplemented by iterative
searches with approximate arithmetic when
exact solutions are impractical.
solve((x
ì
a)
e
^(x)=
ë
x
ù
(x
ì
a),x)
¸
x
=
a or x
=
ë
.567
...
Due to default cancellation of the greatest
common divisor from the numerator and
denominator of ratios, solutions might be
solutions only in the limit from one or both
sides.
(x+1)(x
ì
1)/(x
ì
1)+x
ì
3
¸
2
ø
x
ì
2
so
l
ve
(
entry
(1)
=0,x
)
¸
x
=
1
entry
(
2
)|
ans
(1)
¸
un
d
ef
l
imit
(
entry
(
3
)
,x,
1)
¸
0
For inequalities of types 
‚
, 
, <, or >, explicit
solutions are unlikely unless the inequality is
linear and contains only 
var
.
solve(5x
ì
2
‚
2x,x)
¸
x
‚
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