let X be ComplexNormSpace; :: thesis: for f, g, h being Element of BoundedLinearOperators X,X holds (g + h) * f = (g * f) + (h * f)
let f, g, h be Element of BoundedLinearOperators X,X; :: thesis: (g + h) * f = (g * f) + (h * f)
set BLOP = C_NormSpace_of_BoundedLinearOperators X,X;
set ADD = Add_ (BoundedLinearOperators X,X),(C_VectorSpace_of_LinearOperators X,X);
set mf = modetrans f,X,X;
set mg = modetrans g,X,X;
set mh = modetrans h,X,X;
set mgh = modetrans (g + h),X,X;
(Add_ (BoundedLinearOperators X,X),(C_VectorSpace_of_LinearOperators X,X)) . ((modetrans g,X,X) * (modetrans f,X,X)),((modetrans h,X,X) * (modetrans f,X,X)) = (modetrans (g + h),X,X) * (modetrans f,X,X)
proof
reconsider gg = g as VECTOR of (C_NormSpace_of_BoundedLinearOperators X,X) ;
reconsider hh = h as VECTOR of (C_NormSpace_of_BoundedLinearOperators X,X) ;
A1: gg = modetrans g,X,X by CLOPBAN1:def 10;
A2: hh = modetrans h,X,X by CLOPBAN1:def 10;
reconsider k = (modetrans (g + h),X,X) * (modetrans f,X,X) as VECTOR of (C_NormSpace_of_BoundedLinearOperators X,X) by CLOPBAN1:def 8;
reconsider gf = (modetrans g,X,X) * (modetrans f,X,X) as VECTOR of (C_NormSpace_of_BoundedLinearOperators X,X) by CLOPBAN1:def 8;
reconsider hf = (modetrans h,X,X) * (modetrans f,X,X) as VECTOR of (C_NormSpace_of_BoundedLinearOperators X,X) by CLOPBAN1:def 8;
for x being VECTOR of X holds ((modetrans (g + h),X,X) * (modetrans f,X,X)) . x = (((modetrans g,X,X) * (modetrans f,X,X)) . x) + (((modetrans h,X,X) * (modetrans f,X,X)) . x)
proof
let x be VECTOR of X; :: thesis: ((modetrans (g + h),X,X) * (modetrans f,X,X)) . x = (((modetrans g,X,X) * (modetrans f,X,X)) . x) + (((modetrans h,X,X) * (modetrans f,X,X)) . x)
A3: g + h = gg + hh ;
modetrans (g + h),X,X = g + h by CLOPBAN1:def 10;
then A4: (modetrans (g + h),X,X) . ((modetrans f,X,X) . x) = ((modetrans g,X,X) . ((modetrans f,X,X) . x)) + ((modetrans h,X,X) . ((modetrans f,X,X) . x)) by A1, A2, A3, CLOPBAN1:39;
thus ((modetrans (g + h),X,X) * (modetrans f,X,X)) . x = (modetrans (g + h),X,X) . ((modetrans f,X,X) . x) by Th4
.= (((modetrans g,X,X) * (modetrans f,X,X)) . x) + ((modetrans h,X,X) . ((modetrans f,X,X) . x)) by A4, Th4
.= (((modetrans g,X,X) * (modetrans f,X,X)) . x) + (((modetrans h,X,X) * (modetrans f,X,X)) . x) by Th4 ; :: thesis: verum
end;
then k = gf + hf by CLOPBAN1:39;
hence (Add_ (BoundedLinearOperators X,X),(C_VectorSpace_of_LinearOperators X,X)) . ((modetrans g,X,X) * (modetrans f,X,X)),((modetrans h,X,X) * (modetrans f,X,X)) = (modetrans (g + h),X,X) * (modetrans f,X,X) ; :: thesis: verum
end;
hence (g + h) * f = (g * f) + (h * f) ; :: thesis: verum