HP 48gII - Manual (Page 121)

Page 2-63
Example of flag setting: general solutions vs. principal value
For example, the default value for system flag 01 is General solutions. What
this means is that, if an equation has multiple solutions, all the solutions will be
returned by the calculator, most likely in a list. By pressing the soft
menu key you can change system flag 01 to Principal value. This setting will
force the calculator to provide a single value known as the principal value of
the solution.
To see this at work, first set system flag 01 (i.e., select Principal Value). Press
@@OK@@ twice to return to normal calculator display. We will try solving a
quadratic equation solution, say, t
2 +5t+6 = 0, with command QUAD.
Algebraic mode
Use the following keystroke sequence: ‚N~q (use the up and down
arrow keys, —˜ , to select command QUAD) , press
@@OK@@ .
To enter the equation as the first argument of function QUAD, use the
following keystrokes:
‚O~ „t Q2™+5*~ „t+6——
‚Е0`
‚н ~ „t`
The result is:
Now, change the setting of flag 1 to General solutions: H@FLAGS@
@@OK@@ @@OK@@ . And try the solution again: ——``. The solution
now includes two values:
RPN mode
First set system flag 01 (i.e., Principal Value). Press @@OK@@ twice to return to
normal calculator display. Then, type the quadratic equation as follows:
@ CHK@
@ CHK@