二次积分<img src="https://static.zxtiku.com/wangke/imgs/topic/888d4fae5561146c88bf82ab9083bc97.jpg"/>（）.<br/> A、<img src="https://static.zxtiku.com/wangke/imgs/topic/83047db001cc9bb5725de8dffb3088b8.jpg"/><br/> B、<img src="https://static.zxtiku.com/wangke/imgs/topic/f4dd9009aa78935ea8095ff14db51bee.jpg"/><br/> C、<img src="https://static.zxtiku.com/wangke/imgs/topic/20a223766b008d20dbe1466df3b30187.jpg"/><br/> D、<img src="https://static.zxtiku.com/wangke/imgs/topic/a07187465303c4bd6ba4cb80f7e1948e.jpg"/>