Hello. First post on this forum. I have an assortment of questions, hope somebody can help me.

first: $\displaystyle \int \frac{1}{x^3+x} dx$

second: $\displaystyle \int \sqrt{1-x^2} dx $

third: $\displaystyle \int$$\displaystyle \frac{1}{ sin^2 cot^3} dx$

a hand on these will be very appreciated