Proofgold Proof

pf
Let x0 of type ι be given. Assume H0: RealsStruct x0. Apply RealsStruct_minus_clos with x0, RealsStruct_one x0 leaving 2 subgoals. The subproof is completed by applying H0. Apply RealsStruct_one_In with x0. The subproof is completed by applying H0. ■