# HP Prime for All

**English**Русский

With HP Prime, you can choose whether to operate numerically in the Home view or symbolically using the CAS in the CAS view.
For example, press

- Calculation History
- Tap to select an entry
- Tap twice to copy it to the command line

- Command Line Editor
- 2D textbook format

- Menu Buttons
- Tap to activate
- Context-Sensitive

Things you can do in both CAS and Home views:

- Tap an item to select it or tap twice to copy it to the command line editor
- Tap and drag up or down to scroll through the history of calculations
- Press
Z to retrieve a previous entry or result from the other view - Press the Toolbox key
b to see the Math and CAS menus as well as the Catalog - Press
c to open a menu of easy-to-use templates - Press
J to exit these menus without making a selection - Tap
Sto ▸ ,Copy andShow menu buttons once to activate

**RPN Note:** HP Prime supports RPN entry.
In Home Settings (*Entry* and select `RPN`

.

These workshop materials use the default Textbook setting.

Suppose we wish to explore the series 1+23+45+87+169...

To begin with, we can compute the first few partial sums.

- Press
H to enter the Home view. - Type 1 and press
E - Press
+3/2E - Press
e to cycle through its decimal, proper fraction, and improper fraction forms - Continue as shown to the right until you have the first 5 partial sums

Another approach is to use lists. In the figure to the right, the List `L1`

is first defined to contain
the 1 st partial sum (1), followed by the numerator and denominator of the following term.
The second line adds the next term to the sum, then adds 2 to the numerator and
multiplies the denominator by 2, and stores the result back into list `L1`

.

From there, just pressing

To use the CAS, we observe that the sum can be rewritten symbolically as:

1+23+45+87+169...=∑n=0∞2n1+2n

- Press
K to open the CAS view. - Press
c to open the template menu and select the summation template - To enter
`n=0`

, pressASn>0 - To enter +∞ at the top, tap on the top and press
+ , thenS9 and tap on ∞ - Tap on the right template box and enter the rational expression.
- When you are done, press
E

Home and CAS views are just the tip of the iceberg. Move to HP Apps to explore rest.