Hey everyone. I'm having trouble understanding this example. It says,
Find the inverse of
So far everything is straightforward. Then the solution says:
From the trigonometric formula with and , we obtain
Okay. If I plug x and y into the given trig formula, it comes out as the integral above. However,
I'm confused to how/why they did that because it doesn't make sense (at least not to me).
Any help is appreciated. Thanks in advance!