week 7

This i believe was our last week working on introduction of proofs. We covered proof by cases and reviewed some proofs. Towards the end of the lecture we started on algorithms.

At the beginning of the lecture Mr. Zhang discussed the proof of "if you have a problem in your life, then don't worry"  this was used to introduce cases. the idea was if you have a problem in your life, can you do something about it? case 1 was yes and this proved not to worry about it. case 2 was no and this also proved not to worry about it. The way this was taught was quite funny and I really like the humor that is added into these lectures, it makes it much easier to learn for three hours in a row. 

This then lead to the idea of what makes up a valid proof, which was the union of the cases covering all possibilities. We also went over proofs as a whole and discussed negation introduction and also elimination. I found that  Reviewing these concepts made it easier to tackle assignments and problems in the future.

In this lecture we also began to discuss algorithms. We began by comparing bubble sort and merge sort. This was my first time seeing programs like these and I thought this introduction was good. I learned more about computer programs in general. Like for example running time. I learned that this does not mean the actual amount of time a program takes to run, it is the number of steps taken by the algorithm.