For each of the following integrals, indicate whether integration by substitution or integration by parts is more appropriate, or if neither method is appropriate. Do not evaluate the integrals.

1. $\int\,x\sin x\,dx$

2. $\int\,{x\over 1 + x^{2}}\,dx$

3. $\int\,x e^{x^{2}}\,dx$

4. $\int\,x \cos(x^{2})\,dx$

5. $\int\,{1\over\sqrt{4 x + 1}}\,dx$

(Note that because this is multiple choice, you will not be able to see which parts of the problem you got correct.)