<p>在<img src="https://file.gaojiufeng.cn/learnAppQuestion/dc/7b/dc7b5821040cb1080c33cfb2bce8eaea.jpg" style="width: 100%;height: auto;">中，已知<img src="https://file.gaojiufeng.cn/learnAppQuestion/1f/5e/1f5e8f0f4b422f020a45efc4ee0bfe3f.jpg" style="width: 100%;height: auto;"><img src="https://file.gaojiufeng.cn/learnAppQuestion/a2/0d/a20d08a68de78cec93dd07f124b7bcdb.jpg" style="width: 100%;height: auto;"><br>求<img src="https://file.gaojiufeng.cn/learnAppQuestion/67/98/6798080bb01027562ed3c2d7948062a7.jpg" style="width: 100%;height: auto;"></p>