let r be Element of REAL ; for p, q being 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
|((r * p),q)| = r * ((((f1 . t1) * (g1 . t2)) + ((f2 . t1) * (g2 . t2))) + ((f3 . t1) * (g3 . t2)))
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
|((r * p),q)| = r * ((((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
|((r * p),q)| = r * ((((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 |((r * p),q)| = r * ((((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 )
; |((r * p),q)| = r * ((((f1 . t1) * (g1 . t2)) + ((f2 . t1) * (g2 . t2))) + ((f3 . t1) * (g3 . t2)))
|((r * p),q)| = r * |(p,q)|
by LmAA30;
hence
|((r * p),q)| = r * ((((f1 . t1) * (g1 . t2)) + ((f2 . t1) * (g2 . t2))) + ((f3 . t1) * (g3 . t2)))
by A1, Th51; verum