问题　判断命题“若a∥b ,则a与b的方向相同或相反”的真假。观点一　当a∥b时 ,a与b的方向相同或相反 ,否则 ,a与b不平行 ,故此命题为真。观点二　由于规定了 0与任一向量平行 ,故 0的方向是任意的 ,当a =0时 ,虽然有a∥b ,但由于a的方向是任意的 ,故a与b方向可能既不相同也不 Question To determine if the proposition “if a∥b, then the direction of a and b is the same or opposite” is true or false. Point 1 When a∥b, a and b are in the same or opposite direction, otherwise, a and b are not parallel, so the proposition is true. Since the viewpoint two specifies that 0 is parallel to any vector, the direction of 0 is arbitrary. When a =0, ​​although a∥b, since a direction is arbitrary, the a and b directions may not be the same. nor