Recall earlier calculations
Do 3 calculations. Press 
, type 3, press 
, type 5, press 
, type 2, press 
, and press 
: 21.. Note that no times key is needed between the 3 and the bracket. Second: type 3, press 
, type 5, press , type 2, and press : 17.. Third: type 3, press , type 5, press , type 3, press , type 2, and press : 21.. Press 
and the 
to jump to the oldest calculation: 21.. Press the 
: the second one, 17.. Press the again: the third calculation is 21.. The takes you back: 17.. The history is erased when you press 2nd F CA, turn the calculator off, or change mode.