High-Order Equations From 2Nd To 6Th Degree - Casio FX-7400GII - SOFTWARE VERSION 2-00 User Manual

EQUA
(SIML)
(3)
(SOLV)
• Internal calculations are performed using a 15-digit mantissa, but results are displayed using
a 10-digit mantissa and a 2-digit exponent.
• Simultaneous linear equations are solved by inverting the matrix containing the coefficients
of the equations. For example, the following shows the solution (x, y, z) of a simultaneous
linear equation with three unknowns.
x x a a
y y = = a a
z z a a
Because of this, precision is reduced as the value of the determinant approaches zero. Also,
simultaneous equations with three or more unknowns may take a very long time to solve.
• An error occurs if the calculator is unable to find a solution.
• After calculation is complete, you can press
re-calculate.

2. High-order Equations from 2nd to 6th Degree

Your calculator can be used to solve high-order equations from 2nd to 6th degree.
• Quadratic Equation:
• Cubic Equation:
• Quartic Equation:
1. From the Main Menu, enter the EQUA mode.
2. Select the POLY (Polynomial) mode, and specify the degree of the equation.
You can specify a degree 2 to 6.
3. Sequentially input the coefficients.
• The cell that is currently selected for input is highlighted. Each time you input a coefficient,
the highlighting shifts in the sequence:
a b
• You can also input fractions and values assigned to variables as coefficients.
• You can cancel the value you are inputting for the current coefficient by pressing
any time before you press
to what it was before you input anything. You can then input another value if you want.
–1 –1
b b c c d d
1 1 1 1 1 1 1 1
b b c c d d
2 2 2 2 2 2 2 2
b b c c d d
3 3 3 3 3 3 3 3
ax 2 bx c
+ +
ax bx cx
3 2
+ +
ax 4 bx 3 cx
+ +
c
...
to store the coefficient value. This returns to the coefficient
(REPT), change coefficient values, and then
a
= 0 ( 0)
d a
+ = 0 ( 0)
2 dx e a
+ + = 0 ( 0)
4-2
at