You made a mistake in #1:
after you substitute u = ln(x) you should get:
And in #2 you should make .
Thanks guys. Sorry I didn't respond back until today. Well I have more problems which are harder and I don't really know where to start with some of them.
1.
For this one I don't know here to begina
2.
3.
For these two I was never that good in trig. so it's hard for me to understand where to start.
4.
I'm not really looking for answers but I am looking for how to start these problems. Thank you guys
Substitute
This is an arctangent. First substitute
This was posted before, you just need to note that
Substitute (Do you know Barrow's Rule? When makin' a change of variables you need to get the new integration limits for )