A spherical surface of radius

R

$$has charge uniformly distributed over its surface with a density

Q

$4$

$\backslash$pi

R

$2$

$,$

$$except for a spherical cap at the north pole, defined by the cone

$\backslash$theta

$=$

$\backslash$alpha

$.$

$($

a

$)$

$$Show that the potential inside the spherical surface can be expressed as