Dear all, Is assume(not q = 1, not p = 1, not r = 1 , not p^2 = q , not r^2 = p*q, not r^2 = p , not q^2 = p*r^2); correct if I want to assume that q \neq 1, and so on? When I use q # 1, it does not work. Thank you very much. Best wishes, Jianrong.