Is (|x|)^x > x(|x|)^3?
(1) x2 + 4x + 4 = 0
(2) x < 0
OA is d
I know 1 is suff but how is 2 suff?
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absolute value of x to power x
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faraz_jeddah
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Plugging numbers is quiet fast here..faraz_jeddah wrote:Is (|x|)^x > x(|x|)^3?
(1) x2 + 4x + 4 = 0
(2) x < 0
OA is d
I know 1 is suff but how is 2 suff?
Statement 2: -1, -2,-3 and so on
When X=-1
1^-1>-1 * 1^3 ie 1/1> -1 (yes)
When x=-2
2^-2> -2* 2^3 ie 1/4> -16 ie positive> negative same as in x=-1...(Yes)
this is the trend. thus statement 2 is sufficient.
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Atekihcan
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For statement 2, x is negative.
Now, |x| is always positive.
So, any power of |x| will be also positive.
So, |x|ˣ and |x|³ both are positive.
Now, the left-hand side of the inequality is x*|x|³ = (negative)*(positive) = negative
So, |x|ˣ must be greater than x*|x|³.
So, statement 2 is sufficient.
Now, |x| is always positive.
So, any power of |x| will be also positive.
So, |x|ˣ and |x|³ both are positive.
Now, the left-hand side of the inequality is x*|x|³ = (negative)*(positive) = negative
So, |x|ˣ must be greater than x*|x|³.
So, statement 2 is sufficient.
