Is the answer to this question is 1st option only.
please advice.
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VerbalAttack
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Hi vinviper1,
I & II are obvious and both are correct (satisfy the rule).
As for III, either you expand the equation i.e., apply a@b formula for (a@b)@c and a@(b@c) and make sure both are same or pick numbers to solve faster; i assumed a=1, b=1, c=1 and a=1, b=2, c=3 (second set is just to double check). You can assume any numbers.
both prove that III is also correct.
Cheers
I & II are obvious and both are correct (satisfy the rule).
As for III, either you expand the equation i.e., apply a@b formula for (a@b)@c and a@(b@c) and make sure both are same or pick numbers to solve faster; i assumed a=1, b=1, c=1 and a=1, b=2, c=3 (second set is just to double check). You can assume any numbers.
both prove that III is also correct.
Cheers
