Given, V=k[2x2−y2+z2]
Electric field , E=−(dxdVi^+dydVj^+dzdVk^)
or,E=−k(4xi^−2yj^+2zk^)
or,E(1,1,1)=−k(4i^−2j^+2k^)
Magnitude of electric field=∣E(1,1,1)∣=k2(16+4+4)=k24=2k6