Ninth Lecture - November 4th 2014

Today's term test went horribly. The second proof was exactly the same as the one I did in the assignment but I had no idea how to do it on the test so I think I failed. But then again, it's only worth 6% in the long run so getting 50% on it will still get me 3% of the 6% in the bigger picture, so I guess it's okay. Moving on...

We learned proofs for the big O. There are two tips that I will put on here so I can remember it for future references.

➔ tip 1: c should probably be larger than 3 (the constant factor of the highest-order term)

➔ tip 2: see what happens when n = 1

➔ if n = 1

◆ 3n² + 2n + 5 = 3 + 2 + 5 = 10 = 10n²

◆ so pick c = 10, with B = 1 is probably good

◆ double check for n=2,3,4…, yeah it’s all good

Also, this is super important. I was confused in my tutorial on Monday about choosing the c and B values but this draws it very well - especially if you're a visual learned.

Here is the negation 

Finally, here are the golden rules to doing big-O proofs with "some Calculus".