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markmil2002
Average Member

USA
11 Posts

 Posted - 09/06/2007 :  12:05:15 I cant figure out where to start on this problem.((2e^-x)-(xe^-x))/(1-x^2) > 0

pka

USA
2731 Posts

 Posted - 09/06/2007 :  13:49:10 Because e-x is always positive, it contributes nothing to the problem.Therefore, just solve (2-x)/[(1-x)(1+x)]>0.Here the critical numbers are 2, 1, & -1.Use those to find the intervals where the statement is true.

markmil2002
Average Member

USA
11 Posts

 Posted - 09/06/2007 :  14:25:13 Thanks. I assumed that e could be removed from the equation, but my problem was that I forgot about setting a problem up with the intervals. I took a little brake from math and I'm a little Rusty now, lol.

sahsjing

USA
2399 Posts

 Posted - 09/06/2007 :  18:20:41 quote:Originally posted by markmil2002I cant figure out where to start on this problem.((2e^-x)-(xe^-x))/(1-x^2) > 0Do you know it has the same solution as (2-x)(1-x)(1+x) > 0?
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