Texas Instruments PLUS TI-89 - Manual (Page 67)

50 Chapter 2: Operating the Calculator
02OPER.DOC TI-89/TI-92 Plus: Operating the TI-89/TI-92 Plus (English) Susan Gullord Revised: 02/23/01 1:06 PM Printed: 02/23/01 2:11 PM Page 50 of 44
Using the equation A= p r 2 , use trial and error to find the radius of a
circle that covers 200 square centimeters.
The example below uses 8 as the first guess and then displays the
answer in its approximate floating-point form. You can edit and
reexecute using
7.95 and continue until the answer is as accurate as
you want.
On the TI . 89: On the TI . 92 Plus: Display
8 § j R 2 Л
2 г p ä j R Z 2
¸ 8 § R 2 Ë
2 T R Z 2
¸
¥ ¸ ¥ ¸
A ¥ 8
7.95¸ A ¥ .
7.95¸
You can recall any previous entry that is stored in the history area,
even if the entry has scrolled off the top of the screen. The recalled
entry replaces whatever is currently shown on the entry line. You can
then reexecute or edit the recalled entry.
To recall: Press: Effect:
The last entry
(if you’ve changed
the entry line) 2 ²
once If the last entry is still shown on
the entry line, this recalls the
entry prior to that.
Previous entries 2 ²
repeatedly Each press recalls the entry
prior to the one shown on the
entry line.
For example:
Tip: Editing an entry lets
you make minor changes
without retyping the entire
entry.
Note: When the entry
contains a decimal point, the
result is automatically
displayed in floating-point.
Recalling a Previous
Entry
Note: You can also use the
entry function to recall any
previous entry. Refer to
entry() in Appendix A.
If the entry line contains
the last entry,
2 ²
recalls this entry.
If the entry line is edited
or cleared,
2 ²
recalls this entry.