according to 1)
x* =x
x(x-1) = x
thus x^2 -x =x
=> x^2 -2x = 0
=> x(x-2)=0
INSUFFICIENT
(X - 1 ) * = (X - 2)
(X-1)(X-2) =(X-2)
X^2 -3X +2 =X-2
X^2 -4X +4 =0
(X-2)^2=0
SUFFICIENT
answer is B
tough n confusing
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- arora007
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nehatandon
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perfect solution, arora007!arora007 wrote:according to 1)
x* =x
x(x-1) = x
thus x^2 -x =x
=> x^2 -2x = 0
=> x(x-2)=0
INSUFFICIENT
(X - 1 ) * = (X - 2)
(X-1)(X-2) =(X-2)
X^2 -3X +2 =X-2
X^2 -4X +4 =0
(X-2)^2=0
SUFFICIENT
answer is B












