Week 6 Different kinds of proofs

This week, we learned many different kinds of proofs. Like non-boolean proof, limit proof, and proof for a sequence and also prove by cases.

To prove or disprove a statement about sequence, we just use the skills we learned in last week. But for proving non-boolean statements, we learned some new skills. We are use the non-boolean functions and we can also break down the functions to make it more precise, and then we can only use part of the functions.

Then, we can also proof a statement by cases. If a implication can be true in several different conditions, then we need to prove each of the conditions to show the implication is true. And for some "or" statement, we also need to prove it by cases. For example, there's a general format in notes: