HP 17bII manual How Enter Works, ＋ 6 ：

How ENTER Works

You know that E separates two numbers keyed in one after the other. In terms of the stack, how does it do this? Suppose the stack is filled with a, b, c, and d. Now enter and add two new numbers:

T

Z

Y

X

a

b

c

d

5

	5 ＋ 6 ：
a (lost)		b (lost)
b		c
c		d

d5

5	E 5
Lift		Lift

6

c

d

5

6+

No lift

c

c

d

11

Drop

E replicates the contents of the X-register into the Y-register. The next number you key in (or recall) writes over (instead of lifting) the copy of the first number left in the X-register. The effect is simply to separate two sequentially entered numbers.

Using a Number Twice in a Row. You can use the replicating feature of Eto other advantages. To add a number to itself, key in the number and press E+.

Filling the Stack with a Constant. The replicating effect of E, together with the replicating effect (from T into Z) of stack drop, allows you to fill the stack with a numeric constant for calculations.

Example: Constant, Cumulative Growth. The annual sales of a small hardware company are projected to double each year for the next 3 years. If the current sales are $84,000, what are the annual sales for each of the next 3 years?

1.Fill the stack with the growth rate (2 EEE).

2.Key in the current sales in thousands (84).

E:RPN: The Stack 271

File name : 17BII-Plus-Manual-E-PRINT-030709 Print data : 2003/7/11