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The identity element for the binary oper...

The identity element for the binary operation `**` defined on Q - {0} as `a ** b=(ab)/(2), AA a, b in Q - {0}` is

A

1

B

0

C

2

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C
Given that, `a ** b = (ab)/(2), AA a,b in Q - {0}.`
Let e be the identity element for `**`.
` :. A ** e = (ae)/(2)`
`implies a=(ae)/(2)implies e=2`
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