Let x0 of type ι be given.
Let x1 of type ι be given.
Apply Empty_eq with
SNo_sqrtauxset 0 x0 x1.
Let x2 of type ι be given.
Apply SNo_sqrtauxset_E with
0,
x0,
x1,
x2,
False leaving 2 subgoals.
The subproof is completed by applying H0.
Let x3 of type ι be given.
Assume H1: x3 ∈ 0.