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Baltic Way
1990 Baltic Way
5
5
Part of
1990 Baltic Way
Problems
(1)
True expression for an associative or commutative operation
Source:
4/19/2013
Let
∗
*
∗
be an operation, assigning a real number a * b to each pair of real numbers
(
a
,
b
)
(a, b)
(
a
,
b
)
. Find an equation which is true (for all possible values of variables) provided the operation
∗
*
∗
is commutative or associative and which can be false otherwise.