填空题:设三阶实对称矩阵A的特征值为0，1，2，它们对应的特征向量分别为<img src="http://www.weimei168.com/uploads/202208/1612583852151.png" width="20" height="29" />=(1，1，1)，<img src="http://www.weimei168.com/uploads/202208/16125838583811.png" width="24" height="29" />=(1，<img src="http://www.weimei168.com/uploads/202208/161258386422321.png" width="17" height="19" />，-1)，<img src="http://www.weimei168.com/uploads/202208/161258387131991.png" width="22" height="30" />=(b，-2，1)，则<img src="http://www.weimei168.com/uploads/202208/161258387946371.png" width="17" height="19" />=______，b=______．