Nested calculations – HP 15c User Manual
Page 38
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Section 3: The Memory Stack, LAST X, and Data Storage
Nested Calculations
The automatic stack lift and stack drop make it possible to do nested
calculations without using parentheses or storing intermediate results. A
nested calculation is solved simply as a series of one- and two-number
operations.
Almost every nested calculation you are likely to encounter can be done
using just the four stack registers. It is usually wisest to begin the
calculation at the innermost number or pair of parentheses and work
outward (as you would for a manual calculation). Otherwise, you may need
to place an intermediate result into a storage register. For example, consider
the calculation of
3 [4 + 5 (6 + 7)] :
Keystrokes
Display
6
v 7 +
13.0000
Intermediate result of
(6 + 7).
5
*
65.0000
Intermediate result of
5 (6 + 7).
4
+
69.0000
Intermediate result of
[4 + 5 (6 + 7)].
3
*
207.0000
Final result:
3 [4 + 5 (6 + 7)].
The following sequence illustrates the stack manipulation in this example.
The stack automatically drops after each two-number calculation, and then
lifts when a new number is keyed in. (For simplicity, throughout the rest of
this handbook we will not show arrows between the stacks.)
T
t
z
y
y
y
Z
z
y
x
x
y
Y
y
x
6
6
x
X
x
6
6
7
13
Keys:
6
v
7
+