Page 6-28
The SOLVR sub-menu
The SOLVR sub-menu activates the soft-menu solver for the equation currently
stored in EQ. Some examples are shown next:
Example 1 - Solving the equation t
2
-5t = -4
For example, if you store the equation ‘t^2-5*t=-4’ into EQ, and press
@)SOLVR
,
it will activate the following menu:
This result indicates that you can solve for a value of t for the equation listed at
the top of the display. If you try, for example,
„
[ t ], it will give you the
result t: 1., after briefly flashing the message “Solving for t.” There is a
second root to this equation, which can be found by changing the value of t,
before solving for it again. Do the following: 10 [ t ], then press
„
[ t ].
The result is now, t: 4.0000000003. To verify this result, press the soft menu
key labeled
@EXPR=
, which evaluates the expression in EQ for the current value
of t. The results in this case are:
To exit the SOLVR environment, press
J
. The access to the SOLVE menu is
lost at this point, so you have to activate it once more as indicated earlier, to
continue with the exercises below.
Example 2 - Solving the equation Q = at
2
+bt
It is possible to store in EQ, an equation involving more than one variable,
say, ‘Q = at^2 + bt’. In this case, after activating the SOLVE soft menu, and
pressing
@)ROOT @)SOLVR
, you will get the following screen:
Within this SOLVR environment you can provide values for any of the
variables listed by entering the value in the stack and pressing the
corresponding soft-menu keys. For example, say you enter the values Q = 14,
a = 2, and b = 3. You would use: 14 [ Q ], 2 [ a ], 3 [ b ].
