Texas Instruments TI-89 Titanium Short User Manual page 281

¡, ', "
2 "
dd ¡ mm ss.ss
' "
dd
mm
ss.ss
Returns
This base-60 entry format lets you:
• Enter an angle in degrees/minutes/seconds
without regard to the current angle mode.
• Enter time as hours/minutes/seconds.
'
(prime) 2 È key
variable
'
variable
''
Enters a prime symbol in a differential equation.
A single prime symbol denotes a 1st-order
differential equation, two prime symbols denote a
2nd-order, etc.
_
@
(underscore) ¥
expression unit
_
Designates the units for an
names must begin with an underscore.
You can use pre-defined units or create your
own units. For a list of pre-defined units, refer
to the module about constants and
measurement units. You can press:
@ 2
H
to select units from a menu, or you can type
the unit names directly.
variable
_
When
though it represents a complex number. By
default, without the _ , the variable is treated
as real.
If
variable
variable
Note: You can store a complex number to a
variable without using _ . However, for best
results in calculations such as
cZeros()
Appendix A: Functions and Instructions
2 È
key (¡), key ('),
⇒
expression
A positive or negative number
A non-negative number
A non-negative number
+( /60)+( /3600).
dd mm ss.ss
H
key
expression
9
¥ À
variable has no value, it is treated as
has a value, the _ is ignored and
retains its original data type.
, the _ is recommended.
2 É
key (")
In Degree angle mode:
25°13'17.5" ¸
25°30' ¸
deSolve(y''=y^(ë 1/2) and
y(0)=0 and y'(0)=0,t,y) ¸
2
key
3_m 4 _ft ¸
. All unit
Note: To type 4, press 2 .
Assuming z is undefined:
real(z) ¸
real(z_) ¸
imag(z) ¸
imag(z_) ¸
and
cSolve()
...
25.221
51/2
2øy
3/4
=t
3
9.842...ø_ft
z
real(z_)
0
imag(z_)
275