let S be non empty non void ManySortedSign ; for X being V5() ManySortedSet of S
for A being b1,S -terms MSAlgebra over S holds
( ( for t being Element of A holds t is Element of (Free (S,X)) ) & ( for s being SortSymbol of S
for t being Element of A,s holds t is Element of (Free (S,X)),s ) )
let X be V5() ManySortedSet of S; for A being X,S -terms MSAlgebra over S holds
( ( for t being Element of A holds t is Element of (Free (S,X)) ) & ( for s being SortSymbol of S
for t being Element of A,s holds t is Element of (Free (S,X)),s ) )
let A be X,S -terms MSAlgebra over S; ( ( for t being Element of A holds t is Element of (Free (S,X)) ) & ( for s being SortSymbol of S
for t being Element of A,s holds t is Element of (Free (S,X)),s ) )
A1:
the Sorts of A is MSSubset of (Free (S,X))
by Def6;
then
Union the Sorts of A c= Union the Sorts of (Free (S,X))
by Th1, PBOOLE:def 18;
hence
for t being Element of A holds t is Element of (Free (S,X))
; for s being SortSymbol of S
for t being Element of A,s holds t is Element of (Free (S,X)),s
let s be SortSymbol of S; for t being Element of A,s holds t is Element of (Free (S,X)),s
let t be Element of A,s; t is Element of (Free (S,X)),s
( t in the Sorts of A . s & the Sorts of A . s c= the Sorts of (Free (S,X)) . s )
by A1, PBOOLE:def 2, PBOOLE:def 18;
hence
t is Element of (Free (S,X)),s
; verum