Casio fx-991ES PLUS - Manual (Page 22)

E-21
0 1 2
Current value of X
Input an initial value for X (Here, input 1): 1
To exit SOLVE:
Solution screen
Note: During the time from when you press <(SOLVE) until you exit
SOLVE by pressing , you should use Linear Display input procedures
for input.
Important: • Depending on what you input for the initial value for X (solution
variable), SOLVE may not be able to obtain solutions. If this happens, try
changing the initial value so they are closer to the solution. • SOLVE may not
be able to determine the correct solution, even when one exists. • SOLVE
uses Newton’s Law, so even if there are multiple solutions, only one of them
will be returned. • Due to limitations in Newton’s Law, solutions tend to be
difficult to obtain for equations like the following:
y = sin( x ), y = e x
, y = ' x .
Solution Screen Contents
Solutions are always displayed in decimal format.
Equation (The equation you input.)
Variable solved for Solution
(Left Side) – (Right Side) result
“(Left Side) – (Right Side) result” shows the result when the right side of the
equation is subtracted from the left side, after assigning the obtained value
to the variable being solved for. The closer this result is to zero, the higher
the accuracy of the solution.
Continue Screen
SOLVE performs convergence a preset number of times. If it cannot find a
solution, it displays a confirmation screen that shows “Continue: [=]”, asking
if you want to continue.
Press
to continue or to cancel the SOLVE operation.
To solve y = x 2 – x + 1 for x when y = 3, 7, and 13
5(Y) <(=)
(X)7 (X) 1
<(SOLVE)
Math Math
Math Math