<p>设 <img src="https://learnfile.20230611.cn/learnAppQuestion/b9/9f/b99fc0a90381ce6669a28e9ca4620283.jpg" style="width: 100%;height: auto;">是由方程<img src="https://learnfile.20230611.cn/learnAppQuestion/8e/9f/8e9fb1136ea89230253b5f520ecfe931.jpg" style