Hello!
Haven't been much familiar with these, so I need some help!
I think there's a hint but but I'm not sure if it's right: , anyway I don't know how to use it!
Thanks
You may have to experiment abit. Try a substitution here and there, and if it looks like a deadend to you, try another one. With practice, you will learn to see what substitutions to make on the go. Sometimes you may need to use integration by parts rather than substitution.