HP HP-32S - Correcting Mistakes with L^ll Lastx I

Correcting Mistakes With ill lastx
Wrong One-Number Function. If you execute the wrong one-
number function, useHilastx Ito retrieve the number so you can
execute the correct function. (Press[c] first if you want to clear the
incorrect result from the stack.)
Since H|[%] and Ml %chg Idon't cause the stack to drop, you can re
cover from these functions in the same manner as from one-number
functions.
Example. Suppose that you had just computed In 4.7839 x
(3.879 x 105) and wanted to find its square root, but pressed [£] by
mistake. You don't have to start over! To find the correct result, just
press UQ^st^GI].
Mistakes With Two-Number Functions. If you make a mistake
with a two-number operation
(0, 0,0,0, or [£))/ you can cor
rect it by using M\ lastx I and the inverse of the two-number function
(0 or 0, 0 or 0, {w£} or fg]):
1. Press Hll lastx | 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 LASTXregister.
Then:
• If you had used the wrong function, press [Hi lastx Iagain 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 Hi lastx Ito recover the second number, and execute the func
tion again. (Pressfc1 first if you want to clear the incorrect result from
the stack.)
Example. Suppose you made a mistake while calculating
16 x 19 = 304.
There are three kinds of mistakes you could have made:
42 2: The Automatic Memory Stack