[DTube] How do I integrate tan^2(x)?

I'm in the process of uploading all of my Youtube videos to DTube, where they can be recorded on the Steem blockchain.

In this video, I demonstrate how to find the anti-derivative or the integral of tan²(x). This would normally be quite a difficult integral to solve.

However, the ever powerful trigonometric identities make this an easy problem. By realising that tan²(x)=sec²(x) - 1, the integration of these two terms evaluates to: tan(x) - x.