<p>设向量<img alt="" width="68" height="23" style="width: 100%;height: auto;" src="https://learnfile.20230611.cn/learnAppQuestion/1c/c7/1cc774f480f9817cd2e1a0bc8fc008cd.png"><span style="font-size: 14px;">，则<img alt="" width="15" height="13" style="widt