Q27 of 123 Page 3

Mark the correct alternative in each of the following:

Let * be a binary operation defined on Q+ by the rule for all a, b ∈ Q+. The inverse of 4 * 6 is


As


=8


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


Given


⇒


⇒ e=3


For Inverse element a * b = e = b * a , with ‘b’ being the inverse element a=8 .


Given


⇒ ….(1)


⇒ ….(2)


⇒ is the required inverse element of .

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