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E.g. 3 Solving equations
Solve the equation
4
1 3
x
− =
, giving i) real solutions and ii) complex solutions.
From any of the screen menus, access
the
CFG
menu (see page 329) and ensure
that
Real mode
is selected, as shown
right.
Now use the
SOLVEVX
function, typing:
The
SOLVEVX
function assumes that the active
variable is being used. The default active variable is
X
and if no
=
sign is included then the expression is
assumed to be equal to zero. The related function
of
SOLVE
has a second parameter which allows
you to define the variable to be solved for.
Changing to complex mode in the
CFG
menu
will find the other two imaginary solutions:
E.g. 4 Solving simultaneous equations
Solve the following system of equations:
3
1
x
y
x
y
+ = −
= −
In the CAS, enter:
LINSOLVE(X+Y+3 AND X–Y+1, X AND Y)
. Note
that when entering the two equations you must highlight the first one before
pressing
AND
(obtained via
SHIFT (-)
).
Alternatively you can use
X+Y=-3 AND X=Y-1
instead of the expressions.
The result is:
(X=–2) AND (Y=–1)
LINSOLVE
can be used for any number of simultaneous variables. Step by
step mode will show the solution process using row manipulation of an
augmented matrix.