
theorem AM2:
  for a be light positive Real, b be positive Real holds
  a > b iff log (a,b) > 1
  proof
    let a be light positive Real, b be positive Real;
    1/a < 1/b iff log (1/a,1/b) > 1  by AG2;
    hence thesis by XREAL_1:76,ABO,XREAL_1:118;
  end;
