Since solid is above the cone z >= √x^2 +
y^2 or z^2 >= x^2 + y^2 or 2z^2 >= x^2+z^2 = p^2 or 2p^2 cos^2 φ >=
p^2. Thus cos φ >= 1/√2 since the cone upwards. Thus 0 <= φ
<= pi /4.
On the other hand in spherical coordinates the sphere here
is pcos φ = p^2 so 0 <= cos φ since the solid lies between the sphere. Thus,
making it the two inequalities.
