what's the answer, please?

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by givemeanid » Fri Jul 13, 2007 7:29 pm
a.b = 0
a + b - ab = 0
a + b = ab

Substitute:
(1) b = 2
a + 2 = 2a
a = 2
(2) b = 1
a + 1 = a
This is not possible for any value of a. Hence, correct answer.

You can check rest of the answers. b can take those values.
So It Goes

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Re: what's the answer, please?

by jayhawk2001 » Fri Jul 13, 2007 7:44 pm
a.b = a + b - ab

For b=1, we get a.b = a + 1 - a = 1. So, this cannot be the value of b
as we know a.b=0