Is x negative?
1. x^3(1-x^2) < 0
2. x^2 - 1 < 0
I need help with explanations...
Need help with the explanations
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Is x negative?
1. x^3(1-x^2) < 0
i.e x^3 -x^5 < 0
or x^3 < x^5
here x can be +ve like 2 & x can be -ve like -.2 INSUFF
2. x^2 - 1 < 0
or x^2 <1 i.e x <1> -1
again both -ve & +ve values are possible
INSUFF
Combine
x^3 < x^5 & x <1> -1
so x can be -1<x<0 to satisfy both the conditions
hence -ve SUFF C
1. x^3(1-x^2) < 0
i.e x^3 -x^5 < 0
or x^3 < x^5
here x can be +ve like 2 & x can be -ve like -.2 INSUFF
2. x^2 - 1 < 0
or x^2 <1 i.e x <1> -1
again both -ve & +ve values are possible
INSUFF
Combine
x^3 < x^5 & x <1> -1
so x can be -1<x<0 to satisfy both the conditions
hence -ve SUFF C
Regards
Samir
Samir