How to know when you DON'T need to use substitution (integrals)
We've been doing substitution for a few weeks now, and it's so embedded in my mind that when I look to take an integral, I immediately look for a substitution. I was just trying to do a simple problem and was looking at it for several minutes until I finally realized a substitution was completely unnecessary.
This may seem like a silly question, but what kinds of things separate having to use a u-substitution to not having to use it? What should I be looking for as quick indicators?