若平面区域<img src="https://static.zxtiku.com/wangke/imgs/topic/9fa761de4913f41e89b118046a6e3deb.png"/>关于变量<img src="https://static.zxtiku.com/wangke/imgs/topic/3c37a39aa2caa85351f516e5096144ba.png"/>对称，即<img src="https://static.zxtiku.com/wangke/imgs/topic/2c48d26812066eaa5810c1ec259fef97.png"/>且<img src="https://static.zxtiku.com/wangke/imgs/topic/784c76f860e324e1d88e67083bb5f1af.png"/>，则二重积分<img src="https://static.zxtiku.com/wangke/imgs/topic/ffbf09e6075ed8ac3eb2749ee4120fb6.png"/>.