• The Microsoft Excel COMPLEX function converts coefficients (real and imaginary) into a complex number.
• The complex number can be in either form, x + yi or x + yj.
• The COMPLEX function is a built-in function in Excel that is categorized as an Engineering Function.
• It can be used as a worksheet function (WS) in Excel.

Is all the complex number functions accept “i” and “j” for suffix, but neither “I” nor “J”?. Using uppercase results in the #VALUE! Shows error value. All functions that accept two or more complex numbers require that all suffixes match is that we can do in excel.