# Math Help - Antiderivatives

1. ## Antiderivatives

I'm working on evaluating integrals using part two of the fundamental theorem of calculus and am struggling a bit with antiderivatives. I know the basics, and many of them are easy to find but then I get to functions like 2/the square root of (1-t^2). How would I go about finding an antiderivative of something like that?

2. $\int{\frac{dt}{\sqrt{1-{{t}^{2}}}}}=\arcsin t+k.$

Now, if you want to derive this, put $t=\sin u.$

3. Umm wow, could you explain how you did that though? This just seems way beyond me.