Q7 of 123 Page 3

Mark the correct alternative in each of the following:

Q+ denote the set of all positive rational numbers. If the binary operation on Q+ is defined as a , then the inverse of 3 is


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


Given


⇒


⇒


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


Given


Now for a = 3


⇒ ….(1)


⇒ ….(2)


⇒ is the required inverse element of a=3.

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