Casio CFX-9800G - Page 90

The
following
are
the
operations
that
are
available
from
the
function
menu
at
the
bottom
_of
the
display.
Press
the
function
key
below
the
operation
you
want
to.
perform.
(Fa (2) Linear equation ‘with two unknowns - ‘
(F21(3) Linear equation with three unknowns... . -. . sion ff
F3](4) Linear equation with four unknowns
Fa}(5) Linear equation with five unknowns
F5}(6) Linear equation with six unknowns
MSolving.a Linear Equation with Three Unknowns
Example "To solve the following linear equations for x, y, and z:
Ax+y-2¢=-1
x+6y+3z=1
-5x+4y+2=-7
uM c
While in the Linear Equation Mode (SIM), press 2) (3), because the linear equations be-
ing solved have three. unknowns.
Be).
Coefficient input cells
Value being input into highlighted cell:
Input each coefficient.
e
re Ls]
Ej
Glee
eID
HES
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ONE 4)
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- BEI
aeelal
5
oe [EOLIcrr
Fy
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Each time you press G4, the input value is registered i1 in. the highlighted cell. Each press
of && inputs. values in the following sequence: Sindee uly
coefficient a: > coefficient b: > coefficient c1 > 7
coefficient a2 > coefficient b2 + coefficient a>
coefficient a3 — coefficient bs°-+ coefficient cs
°You can input fractions and ‘value memory contents as coefficients.
After inputting the coefficients, solve the equations.
(sou)
fani¥bn ¥ronZ=dn
Highlighted solution cell value
Internal calculations are performed using a’ 15-digit mantissa, but results are displayed
using a 10-digit mantissa and 2-digit exponent.
*This unit performs simultaneous linear equations’ by placing the coefficients.insidé of
a matrix. Because of this, as the coefficient matrix approaches zero, precision in the
inverse matrix. is reduced and.so precision in the results produced also deteriorates.
For exaniple, the solution for a linear equation with three unknowns would be calculated
as shown below.
x a, b ¢ J-1T a
Y |=] a2 be oe. d,
z ay by Cy d,
¢An “Ma ERROR” occurs whenever the unit is unable to solve the equations.
sFreseing Fi) (RPT) returns to the initial ony | of the Linear Equation Mode.
Depending. on the coefficients: that you use, ; may take considerable time for the
calculation result of simultaneous linear equations to:appear on the display. Failure
of a result to appear immediately does not mean that the unit is not functioning properly.
Changing Coefficients : :
You can change a coefficient sither. before or. after you register it iby pressing Ex.
eTo change a coefficient before registering it with
Press the {9 key to clear the current value and then input another one.
®@To change a coefficient after registering it with
Use the cursor keys to highlight the cell that contains the coefficient that you want to change.
Next, input the value that you want to change to.
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