- THE LAST X REGISTER AND LSTx 
THE LAST X REGISTER AND LSTx

The LAST X register, a separate memory register, preserves the value that was last in the display before execution of a numeric operation*. Pressing g LSTx (LAST X) places a copy of the contents of the LAST X register into the display(X-register). For example:

                     |--------->  lost
 T t ---------->  t -| |------->  z
 Z z ---------->  z ---| |----->  y
 Y y ---------->  y -----| |---> 16
 X 4 --------|-> 16 -------| |->  4
             |               |
Keys: g x^2  |       g LSTx  |
             |               |
             |               |
LAST X: /    |->  4 ---------|->  4

The LSTx feature saves you from having to re-enter numbers you want to use again. It can also assist you in error recovery, such as executing the wrong function or keying in the wrong number.