What sign is W?
1) W^3(1-W^2)<0
2) W^2 - 1<0
The correct answer should be C, but I'm not 100% sure because this problem was only inspired by an OG problem, and not taken directly.
Please help with a "simple" solution. Thanks
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- tomslawsky
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- george.kourdin
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Re: what sine is W?
think it is C
a) insufficient
if w = 2 then (a) < 0
if w = -1/4 then (a) < 0
b) w has to be < 1 for be to be true however since its w^2 w can be either -1/2 or 1/2 so b is insufficient
combine (a) and (b) and we know that w < 1. for (a) to be < 0
w^3 must be < 0 and 1-w^2 must be > 0 so -1<w<0
a) insufficient
if w = 2 then (a) < 0
if w = -1/4 then (a) < 0
b) w has to be < 1 for be to be true however since its w^2 w can be either -1/2 or 1/2 so b is insufficient
combine (a) and (b) and we know that w < 1. for (a) to be < 0
w^3 must be < 0 and 1-w^2 must be > 0 so -1<w<0
- jnelson0612
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