<p>已知空间向量<img src="https://file.gaojiufeng.cn/learnAppQuestion/bd/ff/bdff1c53d067854637fbb29f4b6f3510.jpg" style="width: 100%;height: auto;">则<img src="https://file.gaojiufeng.cn/learnAppQuestion/23/40/2340db7a173734384ce961605536b1d5.jpg" style="width: 100%;height: auto;">（）.</p>