HP 50G, User Manual

Page: 125 / 887

Page 2-65
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
@ @CHK@@
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——
‚Å0`
‚í ~ „t`
The result is:
Now, change the setting of flag 1 to General solutions :
H
@FLAGS@ @ @CHK@@ @@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:
‚O~ „t Q2™+5*~ „t+6——
‚Å0`