Is My Graphing Method for (1/x)<x<1 Correct?

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The discussion centers on solving the inequality (1/x) < x < 1. Initially, the user believes the solution is -1 < x < 1, but others clarify that the correct approach leads to no solution for the first part of the inequality. They demonstrate that for the case where both the numerator and denominator are positive, the conditions contradict each other, resulting in no valid solutions. In the second case, where both are negative, the solution is narrowed down to -1 < x < 0, which is valid under the given constraints. Ultimately, the correct solution for the inequality is confirmed as -1 < x < 0.
garyljc
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Hi all ,
could someone help me out with this
(1/x)<x<1

i tried by drawing the graphs
and separated it in 2 equations
but the answer that i found was -1<x<1
is it correct ?
 
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this equation does not have a solution set

correct me if I'm wrong
if first do the first 2 steps of the equation ,it follows that 1/x < x
therefore x^2>1
second equation will be that x<1
therefore there is no solution
am i correct ?
 
Hi garyljc! :smile:
garyljc said:
1/x < x
therefore x^2>1

am i correct ?

Nope! :smile:

Hint: If a < b and c < 0, is ac < bc? :wink:
 
1/x<x
1/x - x<0
(1-x^2)/x<0
(x^2 - 1)/x>0

case 1: numerator and denominator are positive
numerator
x^2-1>0
(x+1)(x-1)>0
By wavy curve method
x<-1 or x>1
denominator
x>0
so solution for this case is x>1
but x<1 (given in the question)
hence no solution in this case.

case 2: numerator and denominator are negative
x^2-1<0
(x+1)(x-1)<0
By wavy curve method
-1<x<1
x<0
so solution for this case is -1<x<0
but x<1
hence solution for this case is -1<x<0

SO THE ANSWER IS -1<X<0
 
thanks to both lizzie and tim
 
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