To compute surface integral of vector fields needs to find the dot product of the field and its normal vector. This is clear to me.
The question is that why when I chose a multiple of its normal vector(i.e. normal vector was (1,-2,3) and I chose -5(1,-2,3)=(-5,10,-15) ) appears to give me another value when integrated.
I think I make mistake I can’t address. Thank you very much for any advice <3.