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i started with: (x-1) / (x^2+3) - 2/x < 0
then found common denominator, and after simplifying i got a quadratic on top and incomplete cubic on the bottom... it doesn't seem right though...and i can't solve it any further... please help.

2007-10-09 05:13:29 · 2 answers · asked by Maths student 1 in Science & Mathematics Mathematics

2 answers

(x+1) / (x^2+3) < 2/x
Since x^2 + 3 > 0 we can multiply throughout by it
(x+1) < 2*(x^2 + 3)/x

Case 1: If x > 0
x*(x+1) < 2*(x^2 + 3)
x^2 - x + 6 > 0
This is +ve for all x > 0

Case 2: If x < 0
x*(x+1) > 2*(x^2 + 3)
x^2 - x + 6< 0
which is never the case

ANS: x > 0

2007-10-09 05:30:47 · answer #1 · answered by Dr D 7 · 0 0

(x-1)/(x^2+3)-2/x<0
(x^2-x-2x^2-6)/(x(x^2+2)
The sign of the denominator is the sign of x as x^2+3>0
-(x^2+x+6)= always negative
so the solution is x>0

2007-10-09 05:37:20 · answer #2 · answered by santmann2002 7 · 0 0

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