Question 856511
Commutative:
{{{x*y=3xy}}}
{{{y*x=3yx=3xy}}}
So {{{x*y=y*x}}}.
It is commutative.
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{{{(x*y)*z=3(x*y)z=3(3xy))z=9xyz}}}
{{{x*(y*z)=3x(y*z)=3x(3yz)=9xyz}}}
So {{{(x*y)*z=x*(y*z)}}}
It is associative.
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What exactly do you mean by identity for a two input operation?
Do you want {{{x*y=1}}}???