DS 1000 Sec 20 Q20

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DS 1000 Sec 20 Q20

by gviren » Tue Jun 05, 2007 6:10 pm
The OA is C. I think should be B

1) value of the eqn depends on the value of x and n

2) x^2-1 < 0 i.e. 0<x<1

hence it is not less than zero
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Re: DS 1000 Sec 20 Q20

by jayhawk2001 » Tue Jun 05, 2007 9:49 pm
gviren wrote:The OA is C. I think should be B

1) value of the eqn depends on the value of x and n

2) x^2-1 < 0 i.e. 0<x<1

hence it is not less than zero
Can you please clarify on how you arrived at 0<x<1 from x^2-1 < 0 ?

Take x = 0.5 and x = -0.5, both yield x^2-1 < 0. All we know is -1 < x < 1.

Also, I don't see how the answer can be C.

Take n = -1 and try x = 0.5 and x = -0.5. Both satisfy (1) and (2).