HP 48g Graphing Calculator - Manual (Page 214)

18
3. Press Q and then the unknown variable’s white menu key. The
labeled result will be returned to stack level 1 and a message
interpreting the result is displayed at the top of the screen.
4.
Optional: Press
E X P R =
to evaluate the current equation using the
newly computed value for the unknown variable. See “Interpreting
Results” on page 18-3 for more details about intrepreting the
results of the root-finder.
Additional Solving Options in SOLVR
In addition to providing a different environment for finding roots of
equations, expressions and programs, SOLVR allows you a few options
not available in the SOLVE application.
To sequentially solve a series of equations using SOLVR:
1. Enter the equations that you want to use onto the stack in the
order that you will probably want to solve them. Begin with
the equation containing only one unknown variable. The other
equations may begin with additional unknown variables, although
they should have only one variable that remains unknown after
each of the equations preceeding it have been solved.
2. Press repeatedly until the stack pointer indicates the first
equation to be solved.
3.
Press
-i-L
I
ST (
enter
)
to gather the equations into a list.
4. Press (<i^f
solve )
R 0 0 T
EG!
to store the list into
EQ
as
the current “equation.”
5. Enter the SOLVR environment, enter values into the known
variables, and solve for the unknown variable in the first equation
as you would if there were only one equation.
6. Press
N X E Q
(you may need to press (NXT~) one or more times
if there are many variables) to make the “next” equation in the
list into the current equation. The equations are actually rotated
within the list, so that the first equation is now the last, the second
equation now the first, the third now the second, and so forth.
7. Enter any additional known values and solve for the remaining
unknown variable in the equation.
8. Repeat steps 6 and 7 until you have solved for all of the unknown
variables in the series of equations.
You may prefer to use the Multiple Equation Solver instead of SOLVR
for this kind of task (see page 25-6).
18-8 Solving Equations