BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

Line segment of finite length..

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 10
Joined: Thu Oct 24, 2013 10:05 pm

Line segment of finite length..

by sbhawal » Fri Nov 29, 2013 9:24 am
Another of question in GMAT Prep,

Question: Which of the following inequalities has a solution set such that when graphed on the number line is a single line segment of finite length?
A. x^4 ≥ 1
B. x^3 ≤ 27
C. x^2 ≥ 16
D. 2≤mod x≤5
E. 2 ≤ 3x+4 ≤ 6


Answer : E
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 447
Joined: Fri Nov 08, 2013 7:25 am
Thanked: 25 times
Followed by:1 members

by Mathsbuddy » Fri Nov 29, 2013 9:36 am
Any square functions will have symmetry about the y-axis,
so positive "squares" will have 2 solution sets for x^2 > ...

A. x^4 ≥ 1 ELIMINATE (as x^4 = (x^2)^2)
C. x^2 ≥ 16 ELIMINATE

Also:
B. x^3 ≤ 27 is open ended (infinite) ELIMINATE

With a modulus, x could be positive or negative, hence 2 solution sets:
D. 2≤mod x≤5 ELIMINATE

This leaves us with:
E. 2 ≤ 3x+4 ≤ 6

which is simply a finite linear segment (which is easily noticeable even without all the elimination above!)
Top
Post new topic Post Reply
• Page 1 of 1