qqp question1: Does one is forced to conclude that 2X=X\sqrt {2} if series a+b+c+d+…=X? question2: Prove that if A, B, C, and D are sets, then (A ∩ B) X (C ∩ D) = (A X C) ∩ (B X D).Deduce that the cartesian multiplication of sets distributes over the operation of intersection, that is, that (A X B) X C = (AXC) ∩ (BXC) and AX (B∩C)=(AXB)∩(AXC) for all A, B, and C. ?