Is x+1/x-3 <0??
(1)-1<x<1
here x+1 will always be +ve coz x can assume max -ve value of -.99..
& x-3 will always be -ve coz max +ve that x can assume is .99..
hence the expr will be -ve & < 0 SUFF
(2)x^2 - 4<0
here x^ 2 will be +ve & X^2 can assume a max value less than 4 but x can be both +ve as well as -ve e.g. 1.5 or -1.5
say if x =1.5 then x+1/x-3 <0 but if x =-1.5 then x+1/x-3 will be +ve & > 0
Hence INSUFF
A
Inequalities
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samirpandeyit62
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good one samir.
alternatively if you solve x+1/x-3 <0, you will get -1<x<3
1's equation's solution means x should fall in between [-1,1], therefore it satisfies.
2 equation's solution means x should fall in between [-2,2], and that range doesn't fall in the solution range of the given equation. Hence A is the answer.
alternatively if you solve x+1/x-3 <0, you will get -1<x<3
1's equation's solution means x should fall in between [-1,1], therefore it satisfies.
2 equation's solution means x should fall in between [-2,2], and that range doesn't fall in the solution range of the given equation. Hence A is the answer.
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gmatrant
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I have an inequality paranoia!agni_mba wrote:good one samir.
alternatively if you solve x+1/x-3 <0, you will get -1<x<3
1's equation's solution means x should fall in between [-1,1], therefore it satisfies.
2 equation's solution means x should fall in between [-2,2], and that range doesn't fall in the solution range of the given equation. Hence A is the answer.
from your quote if you solve x+1/x-3 <0, you will get -1<x<3
well this is how i tried to solve
multiple both side with (x-3)
so you get (x+1)(x-3)<0
so x <-1 and x<3
so how did -1<x<3 happen.. im sure ive missed something very naive.. can you pls explain
Also i have another doubt if I say x<-1 can it also mean x>1..
Higmatrant wrote:I have an inequality paranoia!agni_mba wrote:good one samir.
alternatively if you solve x+1/x-3 <0, you will get -1<x<3
1's equation's solution means x should fall in between [-1,1], therefore it satisfies.
2 equation's solution means x should fall in between [-2,2], and that range doesn't fall in the solution range of the given equation. Hence A is the answer.
from your quote if you solve x+1/x-3 <0, you will get -1<x<3
well this is how i tried to solve
multiple both side with (x-3)
so you get (x+1)(x-3)<0
so x <-1 and x<3
so how did -1<x<3 happen.. im sure ive missed something very naive.. can you pls explain
Also i have another doubt if I say x<-1 can it also mean x>1..
you have made a small mistake aboove.
multiple both side with (x-3)
you do not get (x+1)(x-3)<0
you get (x+1)<0
but any way I feel u should look at the question and decide how to best solve it. I myself am really bad with number properties and inrqualities, but the more question I look at the better I get. And this forum is great with people helping out all the time. So should be ok, I hope))
