Question

how to do differentiation in scientific calculator

Answer 1

I’ve always disliked that Casio scientific calcs do not have power-off memory protection, so that if your 991MS auto times-out and shuts off from 7 minutes of non-use you have to retype everything back in again, because Casio does not retain your calculation history.

This is why I like the Sharp EL-506X, and the TI-36X Pro, both of which have power-off memory safeguard.