<p>函数<img src="https://file.gaojiufeng.cn/learnAppQuestion/af/a7/afa79417ecd096c3968c378d4d42b012.jpg" style="width: 100%;height: auto;">的定义域为全体实数，且是以5为周期的奇函数，<img src="https://file.gaojiufeng.cn/learnAppQuestion/16/16/161694ecce05b0fd7ba249c8468abc6c.jpg" style="width: 100%;height: auto;">则<img src="https://file.gaojiufeng.cn/learnAppQuestion/8c/66/8c66a78c054b63e729831ef3b465bc3d.jpg" style="width: 100%;height: auto;">等于（）.</p>