Assignment 3 Question 1

The first question of assignment 3 was a fairly easy one luckily. Each member in our group was able to complete the weekly question pretty effectively. We decided to prove:

Ve P R+; Wd P R+; Vx;y P R+; |x -  y| >d =>|x + y| >e

The proof was fairly simple. |x -  y| is always equal to or less than |x + y|, meaning that the later is always greater than d. Using that clue it was a fairly easy question to work out.