Gmat Prep

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Gmat Prep

by alltimeacheiver » Tue May 10, 2011 4:24 am
ques which of the follwoing inequalities has solution thta when graphed on number line is single segment

1 x^4>equal to 1

2 x^3<equal to 27

3 x^2>equal to 16

4 x<eual to |x|<equal to 5
5 2<equal to 3x+4<equal to 6
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by pankajks2010 » Tue May 10, 2011 6:30 am
Well, I am not sure of the question. However, the solution to the inequalities would be as follows:

a) x^4>=1 : The solution set for this inequality is x>=1 and x<=-1

b) x^3<=27 Here, the solution set is x<=3

c) x^2>=16 Just like the first option, the solution for this is x>=4 and x<=-4

d) x<=|x|<=5 for any value of x, x<=|x|, holds true. Thus, the determining criteria is the second part |x|<=5. The solution to which is -5<=x<=5

e) 2<=3x+4<=6 This can be simplified to -2<=3x<=2. Which can be further simplified to -2/3<=x<=2/3.

Now, I am stuck in between option d and e. On exam day, I would go with E.

Please can you share the OA. Thanks!!

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by Anurag@Gurome » Tue May 10, 2011 8:11 pm
alltimeacheiver wrote:ques which of the follwoing inequalities has solution thta when graphed on number line is single segment

1 x^4>equal to 1

2 x^3<equal to 27

3 x^2>equal to 16

4 x<eual to |x|<equal to 5
5 2<equal to 3x+4<equal to 6
Option 4 should be 2 <= |x| <= 5.
This means that 2 <= x <= 5 or -5 <= x <= -2.
This will give us two line segments on the graph.
So, even 4 is eliminated.
The correct answer is 5.
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