let V, W be non empty right_zeroed ModuleStr over INT.Ring ; :: thesis: for f being additiveSAF FrForm of V,W
for w being Vector of W holds f . ((0. V),w) = 0. INT.Ring
let f be additiveSAF FrForm of V,W; :: thesis: for w being Vector of W holds f . ((0. V),w) = 0. INT.Ring
let v be Vector of W; :: thesis: f . ((0. V),v) = 0. INT.Ring
f . ((0. V),v) = f . (((0. V) + (0. V)),v) by RLVECT_1:def 4
.= (f . ((0. V),v)) + (f . ((0. V),v)) by HTh26 ;
hence f . ((0. V),v) = 0. INT.Ring ; :: thesis: verum