What is the magnetic field along the axis and equatorial line of a bar magnet ?

Explanation

The axial line field is `barB_("axial")=(mu_0)/(4pi).(2barmd)/((d^2-l^2)^2)`
On the equatorial line `barB_("equatorial")=-(mu_0)/(4pi).(barm)/((d^2+l^2)^(1//2))`