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r
The unknown does not appear
in
the conditional
expression
in
an
IF function, except
as
the argument of an
S
function.
For
example,
Y=IF(HlB:
exB: B+1e)
cannot
be solved directly for
X.
t
The unknown does
not
appear as an argument
for
any
of
these
functions:
ABS(x)
MOD(x:y)
COMB(x:y)
PERM(xy)
FACT(x)
RND(xy)
FP(x)
SGN(x)
IDIV(x:y)
SPFV(i%:n)
INT(x)
SPPV(i%:n)
IP(x)
rRN(xy)
MAX(x:y)
USFV(i%:n)
MIN(x:y)
USPV(i7o:n)
I
The unknown does
not
appear as the
third
argument (cat)
of
the
DDAYS function.
When the equation contains the unknown raised to a positive,
even
Powef,
there may be more than one solution.
If
the solver can isolate
the unknown,
it
finds
one
of
the solutions using the positive root.
For
example,
(
H-
I
)
^2=25
has
two
solutions.
Th;
Solver algebraically
reduces
this equation to
X
1
:
5 and
calculates
X
:
5.
-To
find
the
other solution, the equation can be rewritten (
I -H
)
^Z=ES.
The
Solver then refurns
X
:
-
4.
'
If
the unknown
can
be isolated
but an
answer
cannot be found, the
HP-275 displays S0LUTI0H HOT
F0UHE.
There are
two
reasons
this might
happen:
r
Rearrangement
causes a
mathematical error. For example, when the
Solver tries
to
isolate
X
in
t
+H
=8, division by 0
occurs.
I
The rearranged
equation violates an algebraic rule. For example, the
equation
E+H-l
rearranges
to
x :
0, which obviously is not
a
solution.
\-,
\,,
\-
\-,
\-
\-
\-
\.
\.,
v
\-,
\./
\-,
\-,
v
\-/
\-,
\-,
\-,
\-.
B:
tore
About the Solyer
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