let I be BinOp of [.0,1.]; :: thesis: ( I is satisfying_(RB) implies ( I is satisfying_(I4) & I is satisfying_(NC) ) )
assume a1: I is satisfying_(RB) ; :: thesis: ( I is satisfying_(I4) & I is satisfying_(NC) )
1 in [.0,1.] by XXREAL_1:1;
hence I is satisfying_(I4) by a1; :: thesis: I is satisfying_(NC)
0 in [.0,1.] by XXREAL_1:1;
hence I is satisfying_(NC) by a1; :: thesis: verum