Anyone here know how to use the EQN mode on the casio fx-115es plus to find solutions to a system of equations involving complex numbers? Also, if that's not possible, what about entering complex numbers to a matrix on this calculator? I haven't been able to figure it out, and searching the web hasn't returned any relevant results.

I'm guessing its possible as this calculator is allowed on the engineering FE exams. So far I've only been able to solve systems using real numbers in EQN mode, and have only been able to perform complex calculations in CMPLX mode.


  • $\begingroup$ support.casio.com/storage/en/manual/pdf/EN/004/… Pg 7 of the PDF seems to hint that this is possible. I'm not digging through the entire manual to figure out how, though, since I don't have that calculator. :) $\endgroup$ – apnorton Aug 4 '14 at 17:12
  • $\begingroup$ Thanks for the link. I didn't find it yet but will dig through the manual a little more. First glance looks like I'm SOL and stuck in CMPLX mode, without access to matrices or system solver. $\endgroup$ – asdf Aug 4 '14 at 23:57

Complex numbers are not supported—on simultaneous equations or on matrices—on the fx-115es plus scientific calculator.

Indeed, no scientific calculator (neither T.I., Sharp or Casio) supports these two kinds of problem solving in CPLX mode.

For that, you will need to choose a graphing calculator with a CAS (Computer Algebra System).

/Silicon Valley Regards


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