code: function(pos) {
          return new Complex(this.x*pos.x - this.y*pos.y, this.y*pos.x + this.x*pos.y);
      }
docs: /*
  Method: prod
  
  Returns the result of multiplying two <Complex> numbers.
  
  Does not alter the original object.
  
  Parameters:
  
  pos - A <Complex> instance.
  
  Returns:
  
  The result of multiplying two complex numbers.