Texas Instruments TI-89 Manual Do Utilizador

Operating the Calculator

 190

 

Clear a–z

Clears (deletes) all single-character variable names in the 
current folder, unless the variables are locked or 
archived. You will be prompted to press 

¸

 to confirm 

the action.

Single-character variable names are often used in 
symbolic calculations such as:
solve(a

¦

2

¦

If any of the variables have already been assigned a 
value, your calculation may produce misleading results. 
To prevent this, you can select 1:Clear a–z before 
beginning the calculation.

NewProb

Places NewProb in the entry line. You must then press 

¸

 to execute the command.

NewProb performs a variety of operations that let you 
begin a new problem from a cleared state without 
resetting the memory:

•

Clears all single-character variable names in the current 
folder (same as 

), unless the variables are 

locked or archived.

•

Turns off all functions and stat plots (

 and 

) in the current graphing mode.

•

Performs 

, 

, 

, 

, 

, and 

.

Restore 
custom 
default

If a custom menu other than the default is in effect, this 
lets you restore the default. Refer to the Calculator Home 
Screen module for information on the custom menu.