Calc Help Pt. II: Integration, Limits & Averages

[Nimmy]

I need help in this problems. please

1. Integration of cos(lnx)

2. Integration of (csc^4 x/2) (cot x)

3. Integration of 2/Sqt. (4-x^2)

4. lim (e^x^2)-1/(2x^2)
x-)0

5. Find the average value of x/(x+3) [-a,a]

 

[Pengwuino]

Well we'd like to see what your thoughts are on these problems. I can offer some hints.

1) Use substitution
2) I'm not exactly sure what the question is
3) Use substitution