NEW: HP 15C Collectors Edition

[John Keith]

(09-24-2023 02:34 PM)carey Wrote:  Just as an aside, the handheld matrix feature I still find amazing, available as a built-in feature starting with full CAS calculators, is symbolic matrices. While not as common as numerical matrices (by a mile!), they manage to show up in several math, science and engineering contexts.

At the risk of dragging this discussion further off topic, what I find more useful than purely symbolic matrices is the ability to use exact integers and fractions in matrices. Not only can we compute the inverse, determinant, etc. without rounding errors, but there is useful insight to be found in the numbers themselves- for instance the smallest denominator in the elements of the matrix inverse. The disadvantage is that exact matrix operations are slower and use more memory than numerical operations.