HP 50g Graphing Calculator - Manual (Page 815)

Page C-4
The same example, corresponding to the RPN operating mode, is shown next:
Approximate vs. Exact CAS mode
When the _Approx is selected, symbolic operations (e.g., definite integrals,
square roots, etc.), will be calculated numerically. When the _Approx is
unselected (Exact mode is active), symbolic operations will be calculated as
closed-form algebraic expressions, whenever possible.
The following screen shows a couple of symbolic expressions entered with an
active exact mode in Algebraic operating mode:
In Algebraic mode, the object entered by the user is shown in the left-hand side
of the screen, followed immediately by a result in the right-hand side of the
screen. The results shown above show the symbolic expressions for ln(2), i.e.,
the natural logarithm of 2, and , i.e., the square root of 5. If the _Numeric
CAS option is selected, the corresponding results for these operations are as
follows:
5