设三阶实对称矩阵的特征值<img src="https://static.zxtiku.com/wangke/imgs/topic/605883ccdcbe51e081703a5b84f8ad5a.jpg"/>，向量<img src="https://static.zxtiku.com/wangke/imgs/topic/71ce5c492fc4198611304ce41134ac57.jpg"/>，<img src="https://static.zxtiku.com/wangke/imgs/topic/4bb73ee237b1cd38ef7735d1d436919b.jpg"/>都是<img src="https://static.zxtiku.com/wangke/imgs/topic/344f877e786318a304548a2a7c88c0fa.jpg"/>的对应于4的特征向量，则<img src="https://static.zxtiku.com/wangke/imgs/topic/344f877e786318a304548a2a7c88c0fa.jpg"/>的对应于特征值<img src="https://static.zxtiku.com/wangke/imgs/topic/30900211292aca0d8118cc55c3537fc6.jpg"/>的特征向量<img src="https://static.zxtiku.com/wangke/imgs/topic/4b64563a10d7176e7bc150650f2ca159.jpg"/>是（）