Integration by substitution is one of the most powerful tools for combating integrals! It allows us to transform a difficult integral into a significantly easier one. In this video we visually show what actually happens when you perform a substitution and how to properly use integration by substitution. Integration video: https://www.youtube.com/watch?v=vcEmFspb8ZU Problem Sheet: https://mathacy.com/problem-sheets Timestamps: 0:00 - Intro 0:37 - Integration by substitution 1:30 - Visualizing integration by substitution 4:12 - Examples (Cancellation) 5:27 - Examples (Substitution for composite functions) 6:04 - Examples (Both) 7:07 - Penalties