let Al be QC-alphabet ; :: thesis: for p being Element of CQC-WFF Al
for x being bound_QC-variable of Al holds
( Ex-bound_in (Ex (x,p)) = x & Ex-the_scope_of (Ex (x,p)) = p )
let p be Element of CQC-WFF Al; :: thesis: for x being bound_QC-variable of Al holds
( Ex-bound_in (Ex (x,p)) = x & Ex-the_scope_of (Ex (x,p)) = p )
let x be bound_QC-variable of Al; :: thesis: ( Ex-bound_in (Ex (x,p)) = x & Ex-the_scope_of (Ex (x,p)) = p )
Ex (x,p) is existential by QC_LANG2:def 13;
hence ( Ex-bound_in (Ex (x,p)) = x & Ex-the_scope_of (Ex (x,p)) = p ) by Def4, Def5; :: thesis: verum