Show that none of operations given above has identity.

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1.Relation and Function

normal

Show that none of the operations given above has identity.

Option A

Option B

Option C

Option D

Solution

An element $e$ $\in Q$ will be the identity element for the operation $^*$

if $a^{*} e=a=e^{*}$ $a$, for all $a \in Q$

However, there is no such element $e \in Q$ with respect to each of the six operations satisfying the above condition.

Thus, none of the six operations has identity.

Standard 12

Mathematics

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