I've recently become the proud owner of a mint HP 48GX
(Black Screen, 2003 build)
However this has gotten me into researching other HP calcs etc.
One thing that has struck me is that whilst the 48GX can be 'expanded' by loading a CAS app like Erable onto it (& eating up 80% of its storage), the 28S seems to have had some sort of simpler 'CAS' built into it already? - Meaning that is could symbolically Simplify and Expand epressions for example. In fact the user manual has a whole section on 'Simplification'.
My question is, the 48 series came out shortly after the 28S & dominated the 90's, but WHY did HP 'Drop' the seemingly Useful 'CAS' features that the older/simpler 28S had? - With HP calcs not getting CAS again until the more current models.
Seems like a backward step by HP? OR 'CAN' the 48GX for example expand & simplify Algebraic equations (WITHOUT installing a prog), but calls it something else?
Look forward to your insights.
Al