HP 33S Owner's Manual

2–8 RPN: The Automatic Memory Stack
File name 33s-E-Manual-1008-Publication(1st).doc Page : 386
Printed Date : 2003/10/8 Size : 13.7 x 21.2 cm
Correcting Mistakes with LAST X
Wrong
One–Num
ber Function
If you execute the wrong one–number function, use
¹ Í
to retrieve the
number so you can execute the correct function. (Press
Å
first if you want to
clear the incorrect result, from the stack.)
Since
m
and
º p
don't cause the stack to drop, you can recover from
these functions in the same manner as from one–number functions.
Example:
Suppose that you had just computed ln 4.7839
×
(3.879
×
10
5
) and wanted to
find its square root, but pressed
#
by mistake. You don't have to start over! To
find the correct result, press
¹ Í ?
.
Mistakes with a Two–number Functions
If you make a mistake with a two–number operation, (
Ù
,
Ã
,
¸
.
¯
,
)
,
¹ b
,
º `
,
'
,
¹ x
,
¹ {
,
m
or
º p
),
you can correct it by using
¹ Í
and inverse of the two–number function.
1. Press
¹ Í
to recover the second number (x just before the operation).
2. Execute the inverse operation. This returns the number that was originally first.
The second number is still in the LAST X register. Then:

If you had used the wrong function, press
¹ Í
again to restore
the original stack contents. Now execute the correct function.

If you had used the wrong second number, key in the correct one and
execute the function.
If you had used the wrong first number, key in the correct first number, press
¹
Í
to recover the second number, and execute the function again. (Press
Å
first if you want to clear the incorrect result from the stack.)
Example:
Suppose you made a mistake while calculating
16
×
19 = 304
There are three kinds of mistakes you could have made:

HP 33S Specifications

General

Type	Scientific
Form factor	Pocket
Product color	Silver
Digits	10 digits
Display number of lines	2 lines
Keyboard type	Alphanumeric
Menus and prompts	Yes

Weight and Dimensions

Dimensions (WxDxH)	157 x 16 x 81 mm