This Casio FX-991CW Advanced Scientific Calculator is a powerful tool for any mathematician or scientist. With over 540 functions, it can handle a wide range of calculations, from simple addition and subtraction to more complex equations and formulas. The calculator is available in black and features a regular key size and display size, making it easy to use and read. The Casio FX-991CW runs on both solar and battery power, making it an ideal choice for users who need a reliable calculator on the go. It is a pocket-sized calculator and is perfect for use in business, office, and industrial settings. The calculator also features calculus functionality, making it an essential tool for anyone who needs to solve complex equations.
Casio FX-991CW the best calculator I have had - so far
Online manual is ok but the pdf version is better.
The physical constants are not explained as to their meaning. Maybe Casio assume if you need the value you'll know the symbol and the units. I noticed at least one value is fractionally different from the latest values.
I hope the next generation of calculators will have units and unit conversions built into the arithmetic e.g. X feet squared times Y psi equals Z kN per metre squared.