Q7 of 123 Page 3

Write the identity element for the binary operation * defined on the set R of all real numbers by the rule for all a, b ∈ R.

The given binary operation is a*b =

Let e be the identity element


Thus, as per the definition of an identity element a*e = a


Applying this in the relation given we have


= a


Or, =1


∴ e =


Thus, the identity element for the given binary operation is .


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