HP 33s Scientific manual How Clear x Works, 6RPN The Automatic Memory Stack

Using a Number Twice in a Row

You can use the replicating feature of ‘to other advantages. To add a number to itself, press ‘›.

Filling the stack with a constant

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

Example:

Given bacterial culture with a constant growth rate of 50% per day, how large would a population of 100 be at the end of 3 days?

Replicates T register

T

1.5 Z

Y

X

1

1.5

1.5

1.5

1.5

1.5

1.5

1.5

100 100

2

1.5

1.5

1.5

150

3

1.5

1.5

1.5

225

4

1.5

1.5

1.5

337.5

5

1.Fills the stack with the growth rate.

2.Keys in the initial population.

3.Calculates the population after 1 day.

4.Calculates the population after 2 days.

5.Calculates the population after 3 days.

How CLEAR x Works

Clearing the X–register puts a zero in the X–register. The next number you key in (or recall) writes over this zero.

There are three ways to clear the contents of the X–register, that is, to clear x:

1.Press ‡

2.Press b

3.Press {c{º} (Mainly used during program entry.)

Note these exceptions:

2–6RPN: The Automatic Memory Stack