SOLVE

[jonmoore]

Further to the other comments, it's important to remember that the Casio model that you're comparing to the HP Prime only works numerically. Much as it has a Solve function, it can only solve numerically, so you're comparing apples with oranges.

One of the nice things about the Prime is that it effectively features two completely separate calculation modes. One for numerical operations and one for symbolic computer algebra operations. However, you have to be careful when calling CAS functions from Home (the numeric Prime personality) as you're not always going to get the answers you expect.

The great thing about the family of Casio calculators you reference (the current model being the fx-991ex), is that they default to exact values. But it's easy to confuse an exact value from the Casio solver as being symbolically derived because it will often match the result from a symbolic solver. But the underlying methodology used by the calculator is very different and has a greater tendency to resolve to approximate answers.