Type in complex numbers of the format 'x+yi' or 'x-yi', real numbers 'x', or imaginary numbers 'yi'.
Bear in mind that 'i' needs to be written as '1i'.

Choose the operation you want from the dropdown box on the left and the number of decimal places you want
the answer rounding to from the text box on the right (a value between zero and twelve).

For example you could type '3+16i' into text box A, '18i' into text box B, then subtract them to get '3-2i'.