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For the binary operation * on Z define...

For the binary operation * on `Z` defined by `a ast b=a+b+1` the identity element is

A

-2

B

0

C

1

D

-1

Text Solution

Verified by Experts

The correct Answer is:
D
If `e` is identity element, then `a∗e=a`
`a+e+1=a`
`e=−1`
Then, `−1 in Z` identity element.
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