Q26 of 123 Page 3

Mark the correct alternative in each of the following:

On the set Q+ of all positive rational numbers a binary operation * is defined by for all a, b ∈ Q+. The inverse of 8 is


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


Given


⇒


⇒ e=2


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 a=8.

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