Gnpth wrote:

What is the value of ab?

1. \(a= b+1\)

2. \(a^2= b+1\)

Each statement individually can be seen is not sufficient.

Let's see what so we get when combineda=b+1 and \(a^2=b+1..... So ...a=a^2.....a^2-a=0....a(a-1)=0\)

Thus a is 0 or 1...

If a =0, a*b=0 irrespective of value of b otherwise b=a-1=-1

If a=1, b=a-1=1-1=0... So a*b=1*0=0So in each case ANSWER is 0

Sufficient

C

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1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372

2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

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