Verifying The Result - HP 32SII Owner's Manual

When SOLVE evaluates an equation, it does it the same way
any "=" in the equation is treated as a " – " For example, the Ideal Gas Law
equation is evaluated as P × V – (N × R × T). This ensures that an equality or
assignment equation balances at the root, and that an expression equation
equals zero at the root.
Some equations are more difficult to solve than others. In some cases, you
need to enter initial guesses in order to find a solution. (See "Choosing Initial
Guesses for SOLVE," below.) If SOLVE is unable to find a solution, the
calculator displays
See appendix C for more information about how SOLVE works.

Verifying the Result

After the SOLVE calculation ends, you can verify that the result is indeed a
solution of the equation by reviewing the values left in the stack:
The X–register (press
solution (root) for the unknown; that is, the value that makes the
evaluation of the equation equal to zero,
The Y–register (press
number should be the same as the value in the X–register. If it is not, then
the root returned was only an approximation, and the values in the X–
and Y–registers bracket the root. These bracketing numbers should be
close together.
The Z– register (press
the root. For an exact root, this should be zero. If it is not zero, the root
given was only an approximation; this number should be close to zero.
If a calculation ends with the
converge on a root. (You can see the value in the X–register — the final
estimate of the root — by pressing
values in the X– and Y–registers bracket the interval that was last searched to
find the root. The Z–register contains the value of the equation at the final
estimate of the root.
If the X– and Y–register values aren't close together, or the Z–register
value isn't close to zero, the estimate from the X–register probably isn't a
7–6 Solving Equations
File name 32sii-Manual-E-0424
Printed Date : 2003/4/24
.
to clear the VIEWed variable) contains the
) contains the previous estimate for the root. This
again) contains this value of the equation at
or
Size : 17 .7 x 25.2 cm
does —
, the calculator could not
to clear the message.) The