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2 items are filed under this topic.
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An associative binary operation |
2008-09-08 |
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From Skye:
Suppose that * is an associative binary operation on a set S. Show that the set H={a E S such that a*x=x*a for all x E S} is closed under *. (We think of H as consisting of all elements of S that commute with every element in S.)
Thanks!
Answered by Harley Weston. |
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Binary operations |
2007-07-30 |
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From jim:
prove or disprove:
Every binary operation on a set consisting of a single element is both commutative and associative.
Answered by Penny Nom. |
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