Proofs

I have to actually think in math classes now. Arrrgh.

No you don't. Proofs are fucking simple.

the only proof they ask in school are theasiest one where u need zero originality and only do it as if u were resolving a problem except u use symbols instead of numbers

Proof just means you have both given data AND the result in front of you. Twice as easy!

I am taking an introduction to analysis course, so they are a bit more complicated than high school geometry. I have never taken a proofs class before and it's different because non-proofs math is just you know the equation and then you do it. With this you have to actually come up with something not shown before.

Also, this is now a help thread!


Using the triangle inequality, prove these:
1) |a-b| <= |a| + |b|
2) | |a| - |b| | <= |a-b|

I figured out the first one. Goes like this:

Given a,b,c, you have |a-b| = |(a-c) + (c-b)|
Using the triangle inequality you get, |(a-c) + (c-b)| <= |a-c| + |c-b|

When c = 0, you get |a-b| <= |a| + |b| QED

Did I do it right? And how do I got the second one?

I got sick of learning math when the courses turned into doing proofs all the time.  Can't be bothered.

#2 sounds like u didnt understand them :)