<p>已知等差数列<img src="https://learnfile.20230611.cn/learnAppQuestion/3e/39/3e39eeba58c51e56295928d84a70da5d.jpg" style="width: 100%;height: auto;">的公差<img src="https://learnfile.20230611.cn/learnAppQuestion/06/93/06935208a2ac63df99feb3d57bfe0b66.jpg" st