On my cheap "dollar store" scientific calculator, it has a 2nd function button named "CPLX". When you press it, the calculator displays some text similar to the "DEG, RAD, GRAD" that says "CPLX". When in this mode, you can't add, subtract, multiply, or divide. The equals button doesn't even work.
What is this and how is it used? I'm wondering if maybe it's for complex numbers, seeing that there's also a "a" and a "b" button next to it.
Best Answer
I know that this is an old question, but I bought a similar calculator and had the same question. The manual that comes with the calculator is a joke and doesn't actually say how to use the a and b buttons.
The calculator that I bought is a 'Jot Scientific Calcultor' from Dollar Tree.
'a' and 'b' are used to enter the first and second values of a paired number, or to switch between the display for a paired number.
The 'CPLX' button toggles the system into complex mode. In complex mode you use the 'a' and 'b' buttons to enter the real and imaginary components of the number, and then the +-*/ functions can be used to operate on the complex values. None of the other functions work (eg no complex exponentials)
(1.4142 + 2i) * (2 + 1.4142i) = (0+ 6i)
-Jon