Are These Relations Reflexive, Antisymmetric, and Transitive?

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Homework Statement


Are these two relations reflexive, antisymmetric, transitive?

1. (w,x)<=(y,z) iff w+x <= y+z

2. (w,x)<=(y,z) iff w+x <= y+z AND w<y

Homework Equations





The Attempt at a Solution



1. reflexive - yes; antisymmetric - no; transitive - yes;

2. reflexive - yes; antisymmetric - yes; transitive - yes;
 
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would you say the second is reflexive?
 
lanedance said:
would you say the second is reflexive?

With the way I wrote it no. But I actually made a typo, it should be w+x <= y+z AND w<=y. So I'd say yes
 
ok, would that change anything else?
 
lanedance said:
ok, would that change anything else?

No, I think #2 would still be antisymmetric and transitive
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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