Question

electric field due to an electric dipole at a point lying on the axial and at the equitorial line​

Answer 1

Resultant direction of electric field in transversal line. The direction of electric field on the equatorial line is always opposite to the direction of dipole moment. So we can say − Dipole Electric field depletes faster then electric field by a point charge.

Answer 2

The NCERT formula is correct if used with vector notation as the direction of electric dipole moment is from -q(negative charge) to +q(positive charge) and the resultant electric field at any point on equatorial line is in direction opposite to the electric dipole moment so negative sign is used. The other formula which does not include negative sign is applicable to calculate the magnitude(not direction) of electric field.