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nafiul9090
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1) x^2<1;nafiul9090 wrote:is x between 0 and 1?
1) x^2 is less than 1
2) x^3 is positive
OA later
x^2-1<0;
(x-1)(x+1)<0;
-1<x<1;
now x can assume both positive and negative values lying between -1 and 1; i.e. x can be either -0.5 or 0.7, as we can't say with surety whether x is lying between 0 and 1 hence 1 alone is not sufficient to answer the question.
2) x^3 is positive; i.e x>0; because now here x can either lie between 0 and 1 or it can be greater than 1 hence 2 alone is not sufficient to answer the question.
combining 1 and 2 we have;
from -1<x<1; and from 2 x>0;
therefore x will lie between 0<x<1;(because here we are looking for a common solution that will satisfy both 1 and 2) hence C












