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A binary operation * is defined on the set of positive integers is such x*y = 2x-3y+2 ...

A binary operation * is defined on the set of positive integers is such x*y = 2x-3y+2 for all positive integers x and y. The binary operation is
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  • A Commutative and close on the set of positive integers
  • B Neither commutative nor closed on the set of ppositive integers
  • C Commutative but not closed on the set of positive integers
  • D Not cummutative but closed on the set of positive integers
Correct Answer: Option B
Explanation:
X * Y = 2X - 3Y + 2
2*3 = 2(2) - 3(3) + 2
=4-9+2
= -3
But -3 does not belong to positive integer

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