Q23 of 123 Page 3

Mark the correct alternative in each of the following:

Consider the binary operation * defined on Q - {1} by the rule a * b = a + b – ab for all a, b ∈ Q – {1}. The identity element in Q – {1} is


For Identity element a * e = a = e * a, with ‘e’ being the identity element.


Given a * b =a + b - ab


⇒ a * e =a + e – ae


=a


⇒ e(1-a) =0


⇒ e=0

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