Does ab = a^2

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Does ab = a^2

by jbsocal » Tue Dec 18, 2012 9:55 pm
Does ab = a^2

(1) a^2 = b ^2

(2) a^3 = b ^3



[/spoiler]B

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by puneetkhurana2000 » Tue Dec 18, 2012 10:38 pm
Is ab = a^2 ?, This can be rephrased as Is a = 0 or a = b ?

Statement 1) a^2 = b ^2

a = +b or - b, Not Sufficient!!

Statement 2) a^3 = b ^3

a can only be equal to b, Sufficient!!!

Answer B.

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by Anindya Madhudor » Tue Dec 18, 2012 10:41 pm
Statement I:

Possible solutions are a= b or a=-b. So, ab= a^2 or (-a^2). We cannot definitely answer the question. Not sufficient.

Statement II:

a^3 = b^3 means a=b. So, ab=a^2. Sufficient.