which is greater 2+3i or 9+1i ? & why

WE CANNOT TELL THAT WHICH ONE IS GREATER BECAUSE i(iota) is an imaginary function it doesnot have a fixed value.

Technically, complex numbers cannot be compared regarding size/(greater/smaller). Only the absolute values can be compared, not the numbers themselves. This is a postulate.

9+1i is greater than 2+3i since complex numbers are like vectors only...

9+i is greater than 2+3i ,because we first give importance to real part .
in this 9 >2 ,

so we can easly  say that 9+i is greater.