<img src="https://zk.995w.com/lqwvjeImg/8a/8a10de8c94533d8c77f530ef4a2779c5.png" style="font-size: 20px;" >是平面<img src="https://zk.995w.com/lqwvjeImg/49/496be68cfcd5d56738c48727ce19e09c.png" style="font-size: 20px;" >在第一封限内的部分,则曲面积分<img src="https://zk.995w.com/lqwvjeImg/5c/5c9d9ab9993b354841bb9add0f16fcd3.png" style="font-size: 20px;" >( )<br>·<img src="https://zk.995w.com/lqwvjeImg/75/751e4d6af885882d494b2ceb00ea8068.png" ><br>·<img src="https://zk.995w.com/lqwvjeImg/ef/ef0bc1f627ba7265800df3922388cb6b.png" ><br>·<img src="https://zk.995w.com/lqwvjeImg/6b/6b41e7bce006a84508490fedda2beeba.png" ><br>·<img src="https://zk.995w.com/lqwvjeImg/a2/a27a1fca3f12eb01db84eaae76884e33.png" >