let p be Element of CQC-WFF ; :: thesis: for x being bound_QC-variable holds
( Ex-bound_in (Ex x,p) = x & Ex-the_scope_of (Ex x,p) = p )
let x be bound_QC-variable; :: 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