设积分, 交换积分次序后, 积分为。( ）http://image.zhihuishu.com/zhs/onlineexam/ueditor/201803/864b8fd140404405a3f0c50977552895.png

A . A B . B C . C D . D

A .https://assets.asklib.com/psource/2015102917011683633.jpg B .https://assets.asklib.com/psource/2015102917014467452.jpg C .https://assets.asklib.com/psource/2015102917032793192.jpg D .https://assets.asklib.com/psource/2015102917034437496.jpg

A .https://assets.asklib.com/psource/2015102908463839977.jpg B .https://assets.asklib.com/psource/2015102908465216566.jpg C .https://assets.asklib.com/psource/2015102908470733418.jpg D .https://assets.asklib.com/psource/201510290847219913.jpg

A . A、50％以上 B . B、最大值上 C . C、最小值上 D . D、任意值上

A . 收敛（对任何q） B . 发散（对任何q） C . 当q＜1时收敛，当q≥1时发散 D . 当q＜1时发散，当q≥1时收敛

A . 收敛（对任何p） B . 发散（对任何p） C . 当p≤1时收敛，当p＞1时发散 D . 当p≤1时发散，当p＞1时收敛

A .https://assets.asklib.com/psource/2015102917174668011.jpg B .https://assets.asklib.com/psource/2015102917180844389.jpg C .https://assets.asklib.com/psource/2015102917183436761.jpg D .https://assets.asklib.com/psource/2015102917185022062.jpg

A .https://assets.asklib.com/psource/2015102914095653127.jpg B .https://assets.asklib.com/psource/2015102914101219015.jpg C .https://assets.asklib.com/psource/2015102914103264282.jpg D .https://assets.asklib.com/psource/2015102914105028342.jpg

<img src='https://img2.soutiyun.com/ask/2020-02-11/950260245054112.png' />

A、Integrate[sqrt[Exp[x]]/sqrt[Exp[x]+Exp[-x]],{x,0,1.}] B、Integrate[Sqrt[exp[x]]/Sqrt[exp[x]+exp[-x]],{x,0,1.}] C、Integrate[Sqrt[Exp[x]]/Sqrt[Exp[x]+Exp[-x]],{x,0,1.}] D、Integrate[Sqrt[Exp[x]]/Sqrt[exp[x]+exp[-x]],{x,0,1.}]

<img src='https://img2.soutiyun.com/ask/2020-08-14/96624425787688.png' />

二次积分<img src='https://img2.soutiyun.com/shangxueba/ask/17676001-17679000/17676154/2015102917004746434.jpg' />交换积分次序后的二次积分是（）。 A．<img src='https://img2.soutiyun.com/shangxueba/ask/17676001-17679000/17676154/2015102917011683633.jpg' /> B．<img src='https://img2.soutiyun.com/shangxueba/ask/17676001-17679000/17676154/2015102917014467452.jpg' /> C．<img src='https://img2.soutiyun.com/shangxueba/ask/17676001-17679000/17676154/2015102917032793192.jpg' /> D．<img src='https://img2.soutiyun.com/shangxueba/ask/17676001-17679000/17676154/2015102917034437496.jpg' />

<img src='https://img2.soutiyun.com/ask/2021-01-10/97914323460899.png' />

设积分区域B<img src='https://img2.soutiyun.com/ask/2019-07-12/931776883064311.png' />，则二重积分<img src='https://img2.soutiyun.com/ask/2019-07-12/931776894920166.png' />=()。 A.<img src='https://img2.soutiyun.com/ask/2019-07-12/931776917633624.png' /> B.<img src='https://img2.soutiyun.com/ask/2019-07-12/931776930144516.png' /> C.<img src='https://img2.soutiyun.com/ask/2019-07-12/931776945871192.png' /> D.<img src='https://img2.soutiyun.com/ask/2019-07-12/931776970580355.png' />

A、（A） B、（B） C、（C） D、（D）

将二重积分<img src='https://img2.soutiyun.com/ask/2021-01-19/979920905720396.png' />按两种次序化为累次积分，积分区域D分别给定如下： (1)D由曲线y=x³与直线y=1，x=-1所围成，如图7-21所示; (2)D由圆x²+y²≤4所围成，如图7-22所示; (3)D由直线y=2x，y=0及x=3所围成，如图7-23所示. <img src='https://img2.soutiyun.com/ask/2021-01-19/97992096192361.png' />

设积分区城为D=|(x,y)}0≤x≤1,0≤y≤1}.计算二重积分 <img src='https://img2.soutiyun.com/ask/2021-01-10/979148559653565.png' />

<img src='https://img2.soutiyun.com/ask/2020-12-22/977523701056398.png' />

设L为椭圆<img src='https://img2.soutiyun.com/ask/2020-11-04/973329011013762.png' />,L的长度为l,则对弧长的曲线积分<img src='https://img2.soutiyun.com/ask/2020-11-04/973329024394527.png' />=().

是 否

把二重积分<img src='https://img2.soutiyun.com/ask/2020-12-28/978029335533442.png' />在直角坐标系中分别以两种不同的次序化为累次积分,其中(σ)为 <img src='https://img2.soutiyun.com/ask/2020-12-28/978029405558447.png' />