Texas Instruments TI-89 Titanium Short User Manual page 169

cos()
@
2 X key
expression1
cos(
) ⇒
list1
cos(
expression1
cos(
argument as an expression.
list1
cos(
elements in
Note: The argument is interpreted as either a
degree or radian angle, according to the current
angle mode setting. You can use ó or ô to
override the angle mode temporarily.
squareMatrix1
cos(
Returns the matrix cosine of
not
the same as calculating the cosine of each
element.
When a scalar function f(A) operates on
squareMatrix1
algorithm:
1. Compute the eigenvalues (l
eigenvectors (V
squareMatrix1
cannot have symbolic variables that have not
been assigned a value.
2. Form the matrices:
B =
3. Then A = X B Xê and f(A) = X f(B) Xê. For
example, cos(A) = X cos(B) Xê where:
cos (B) =
All computations are performed using floating-
point arithmetic.
cosê ()
@
¥ R key
expression1
cosê (
) ⇒
list1
cosê (
cosê (
is expression1
cosê (
each element of
Note: The result is returned as either a degree or
radian angle, according to the current angle
mode setting.
Appendix A: Functions and Instructions
H
) ⇒
expression
list
returns the cosine of the
)
returns a list of the cosines of all
)
.
list1
) ⇒
squareMatrix
squareMatrix1
(A), the result is calculated by the
) of A.
i
must be diagonalizable. Also, it
 
l 1 0 ... 0
 
0 l 2 ... 0
and X = [V
 
0 0 ... 0
 
0 0 ... l n

λ
cos( ) 0
1

λ
0 cos( )

2

0 0


0 0
H
) ⇒
expression
list
returns the angle whose cosine
expression1
)
as an expression.
list1 returns a list of the inverse cosines of
)
.
list1
X key
In Degree angle mode:
cos((p/4)ô ) ¸
cos(45) ¸
cos({0,60,90}) ¸ {1
In Radian angle mode:
cos(p/4) ¸
cos(45¡) ¸
In Radian angle mode:
. This is
cos([1,5,3;4,2,1;6,ë 2,1]) ¸
) and
i
,V , ... ,V ]
1 2 n

K
0

K
0


K
0

λ
K

cos( )
n
2 R key
In Degree angle mode:
cosê (1) ¸
In Radian angle mode:
cosê ({0,.2,.5}) ¸

.212... .205...

.160... .259...

ë.090...
.248...
p
{ ...
1.369 1.047
2
‡2
2
‡2
2
1/2 0}
‡2
2
‡2
2

.121...

.037...

.218...
0
... }
163