Inequality Calculations
You can use the procedure below to solve a 2nd, 3rd, or 4th degree
inequality.
1. Press
, select the Inequality Mode icon, and then press
.
2. On the dialog box that appears, use a number key (
to
) to
specify the degree of the inequality.
3. On the menu that appears, use keys
through
to select the
inequality symbol type and orientation.
4. Use the Coefficient Editor that appears to input coefficient values.
• To solve
x
2
+ 2
x
− 3 < 0, for example, input the following for the
coefficients (
a
= 1,
b
= 2,
c
= -3): 1
2
3
.
• Pressing
will clear all of the coefficients to zero.
5. After all the values are the way you want, press
.
• This will display the solutions.
• To return to the Coefficient Editor while the solutions are displayed,
press
.
To change the Inequality Type:
Pressing
(Polynomial) displays a
dialog box that you can use to select an inequality degree. Changing the
degree of an inequality causes the values of all Coefficient Editor
coefficients to become zero.
Inequality Mode Calculation Examples
3
x
3
+ 3
x
2
−
x
>
0
(Polynomial)
(3
rd
degree inequality)
(ax
3
+bx
2
+cx+d>0)
3
3
1
Note
• Solutions are displayed as shown in the
screen shot nearby when something
other than MathI/MathO is selected for
the Input/Output setting on the setup
menu.
• “All Real Numbers” appears on the solution screen when the solution of
an inequality is all numbers (such as
x
2
≧
0).
• “No Solution” appears on the solution screen when no solution exists for
an inequality (such as
x
2
< 0).
Ratio Calculations
The Ratio Mode lets you determine the value of X in the ratio expression A :
B = X : D (or A : B = C : X) when the values of A, B, C and D are known. The
following shows the general procedure for using Ratio.
1. Press
, select the Ratio Mode icon, and then press
.
2. On the menu that appears, select
(A:B=X:D) or
(A:B=C:X).
3. On the Coefficient Editor screen that appears, input up to 10 digits for
each of the required values (A, B, C, D).
30
