A system of charged particles exist in 3-D space. The potential due to this system along x direction is given by kx2,where k is a positive constant. What is the electric field along x-axis due to this system of charged particles?
1
\( -2kx \hat i\)
2
\( 2kx \hat i\)
3
\( -kx \hat i\)
4
\( kx \hat i\)