let p, q be Element of REAL 3; for f1, f2, f3, g1, g2, g3 being PartFunc of ,
for t1, t2 being Real st p = (VFunc f1,f2,f3) . t1 & q = (VFunc g1,g2,g3) . t2 holds
p + q = |[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]|
let f1, f2, f3, g1, g2, g3 be PartFunc of ,; for t1, t2 being Real st p = (VFunc f1,f2,f3) . t1 & q = (VFunc g1,g2,g3) . t2 holds
p + q = |[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]|
let t1, t2 be Real; ( p = (VFunc f1,f2,f3) . t1 & q = (VFunc g1,g2,g3) . t2 implies p + q = |[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]| )
assume A1:
( p = (VFunc f1,f2,f3) . t1 & q = (VFunc g1,g2,g3) . t2 )
; p + q = |[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]|
p + q =
|[((p . 1) + (q . 1)),((p . 2) + (q . 2)),((p . 3) + (q . 3))]|
by Lm4
.=
|[((f1 . t1) + (q . 1)),((p . 2) + (q . 2)),((p . 3) + (q . 3))]|
by A1, Th34
.=
|[((f1 . t1) + (q . 1)),((f2 . t1) + (q . 2)),((p . 3) + (q . 3))]|
by A1, Th34
.=
|[((f1 . t1) + (q . 1)),((f2 . t1) + (q . 2)),((f3 . t1) + (q . 3))]|
by A1, Th34
.=
|[((f1 . t1) + (g1 . t2)),((f2 . t1) + (q . 2)),((f3 . t1) + (q . 3))]|
by A1, Th34
.=
|[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (q . 3))]|
by A1, Th34
.=
|[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]|
by A1, Th34
;
hence
p + q = |[((f1 . t1) + (g1 . t2)),((f2 . t1) + (g2 . t2)),((f3 . t1) + (g3 . t2))]|
; verum