下列不定积分中，常用分部积分法计算的是（　）．

<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/2-3/image037.png" alt="" align="middle">

<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/2-3/image038.png" alt="" align="middle">

<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/2-3/image039.png" alt="" align="middle">

<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/2-3/image040.png" alt="" align="middle">