设函数<img src="https://static.zxtiku.com/wangke/imgs/topic/6b530befec8a210932374e9ab0ff4c1e.png"/> 在点<img src="https://static.zxtiku.com/wangke/imgs/topic/9417410870e4940a1c100cd34903f032.png"/> 处的可导,<img src="https://static.zxtiku.com/wangke/imgs/topic/7ec25e5b651544db7165999c11c7f8aa.png"/> 和<img src="https://static.zxtiku.com/wangke/imgs/topic/22dfca616e765f9757ab8de8bd4a3285.png"/> 分别是自变量和因变量的增量,<img src="https://static.zxtiku.com/wangke/imgs/topic/4f76f3f874401bb5ce7c9febc949d5c1.png"/> 为该函数在点<img src="https://static.zxtiku.com/wangke/imgs/topic/8092efc74e4ab761e72f09603127ba44.png"/> 处的微分,且<img src="https://static.zxtiku.com/wangke/imgs/topic/bce95b4f84b15057548db360e92bdf7e.png"/> ,则<img src="https://static.zxtiku.com/wangke/imgs/topic/e3452c2fbe2fd900cd3acf5c2566837d.png"/> ( ).