How to sove the complex equation in fx 500? - Casio FX-115ES Scientific Calculator

SOURCE: want to solve quadratic equations on my casio 3650p super fx

Hello,
In your manual, Appendix Program Library, (Page A1) you have the listing of the problem to solve the quadratic equation. Type it in your calculator and execute it.


Hope it helps.

SOURCE: In complex number mode, how to get out?

"Is there anything that I can do about this to stop my answers being complex numbers when solving cubic equations?"
You are making an assumption that is unwarranted.Namely that a cubic equation must necessarily have 3 real roots. This is not the case.

Let your equation be

If coefficients are complex you should expect some complex roots. Right?
If the coefficients are REAL then depending on the discriminant

you can have three cases
DELTA positive : three distinct real roots
DELTA=0 , the equation has a multiple root and all roots are REAL
DELTA negative: the equation has ONE real root and 2 complex roots that are complex conjugate of each other.

It suffices to look at the Tartaglia/Cardano expressions of the roots to know that more often than not there is going to be complex roots.

SOURCE: Hello How to solve complex

The simultaneous equation solver requires the coefficients to be real. Similarly matrices must have real coefficients.
Your only alternative is to express each of A and B as a real part and imaginary part.
A= x1+iy1
B=x2+iy2.
Substitute x1+iy1 for A in the two equations. Substitute x2+iy2 for B in the two equations. Do the algebra. Gather real parts and gather imaginary parts. Split each original equation into two equations: One equation comes from setting Real Part of left side = real part of right side (1); the other equations comes from setting the imaginary part of left side= imaginary part of right side (here 0).

Do the same procedure for the 2nd original equation.
At the end of the process you will have 4 coupled linear equations in the 4 unknowns (x1,y1,x2,y2).

Then you might want to use the calculator to solve the derived system. Once you have x1,y1,x2,y2 you reconstruct A=x1+iy1, etc.