let X, Y be RealNormSpace; for f being Function of X,Y holds
( f is Lipschitzian LinearOperator of X,Y iff f * ((IsoCPNrSP X) ") is Lipschitzian LinearOperator of (product <*X*>),Y )
let f be Function of X,Y; ( f is Lipschitzian LinearOperator of X,Y iff f * ((IsoCPNrSP X) ") is Lipschitzian LinearOperator of (product <*X*>),Y )
thus
( f is Lipschitzian LinearOperator of X,Y implies f * ((IsoCPNrSP X) ") is Lipschitzian LinearOperator of (product <*X*>),Y )
by LOPBAN_2:2; ( f * ((IsoCPNrSP X) ") is Lipschitzian LinearOperator of (product <*X*>),Y implies f is Lipschitzian LinearOperator of X,Y )
assume
f * ((IsoCPNrSP X) ") is Lipschitzian LinearOperator of (product <*X*>),Y
; f is Lipschitzian LinearOperator of X,Y
then reconsider g = f * ((IsoCPNrSP X) ") as Lipschitzian LinearOperator of (product <*X*>),Y ;
rng (IsoCPNrSP X) = the carrier of (product <*X*>)
by FUNCT_2:def 3;
then A1:
((IsoCPNrSP X) ") * (IsoCPNrSP X) = id the carrier of X
by FUNCT_2:29;
g * (IsoCPNrSP X) =
f * (((IsoCPNrSP X) ") * (IsoCPNrSP X))
by RELAT_1:36
.=
f
by A1, FUNCT_2:17
;
hence
f is Lipschitzian LinearOperator of X,Y
by LOPBAN_2:2; verum