Question | Answer |
Commutative | For every x,y belonging to F, there is a x+y=y+x and a x*y=y*x |
Associative | For every x,y,z belonging to F there is:
(x+y)+z=x+(y+z) and
(x*y)*z=x*(y*z) |
Closure | For every x,y belonging to F there is x+y belonging to F and x*y belonging to F. |
Well-Ordering Principle | -Every non-empty sub set of Natural Numbers has a least element.
-If M <= Natural Numbers, then there exists R belonging to M so that R <=a for ever a belonging to M. |
Induction Principle | (Natural Numbers)
Suppose P(n) is a statement about:
n belonging to Natural Numbers, If we can show
1.P(1) is true.
2.Whenever P(n) is true then P(n+1) is true.
Then P(n) is true for all n. |
Ordered Field | A field F that is an ordered set with the following additional properties:
1. If x>0 and y>0 then x+y>0
2. If x>0 and y>0 then x*y>0
3. x<y if and only if y-x>0 |
Order | An order on a set S is a relation that satisfies the following:
1. If x,y belongs to S, then exactly one of x<y, x=y, or y<x is true.
2. For all x,y,z belonging to S, if x<y and y<z then x<z. |
Field | A nonempty set F of objects that has two operations, addition and multiplication, that satisfy the following properties:
-Closure
-Associative
-Identity
-Inverses
-Distributive
-Commutative |
Distributive | For every x,y,z belonging to F there is x*(y+z)= x*y + x*z |
Inverses | For every x belonging to F there is -x belonging to F so that x+(-x)=0
For each x belonging to F there is a 1/x belonging to F so that x* (1/x) = 1, x!=0. |
Identity | For x belonging to F there exists 0 belonging to F so that x+0=x and there exists 1 belonging to F so that x*1=x. |