R , : , , , , , , :
I. ( ) a + b = b + a;
II. ( ) a + (b + c) = (a + b) + c;
III. ( ) a b R a + x = b ( , ) , . . , a + c = b;
IV. ( ) ab = ba;
"" . .
V. ( ) a(bc) = (ab)c;
VI. ( )
(a + b)c = ac + bc.
:
1. .
2. .
3. .
4. .
5. , 0.
6. , n.
7. ( ).
8. , a b .
, , III.
9. R. , . , , R,
10. (a, b) , :
.
, ( ) . , , +1 1. ( 0). , - .
P, :
VII. ( ) , , ( ) , . . , .
VIII. , .
1-10 2, 3 4, . . , , . 5 VII , a ≠ 0, VIII. VII.
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