It is currently 16 Oct 2017, 19:12

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If 0 < x ≤ 1, then which one of the following is the maximum

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Manager
Manager
avatar
B
Joined: 27 Jul 2011
Posts: 61

Kudos [?]: 74 [0], given: 15

If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 21 Nov 2013, 03:22
5
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

76% (01:10) correct 24% (00:50) wrong based on 208 sessions

HideShow timer Statistics

If 0 < x ≤ 1, then which one of the following is the maximum value of (x – 1)^2 + x ?

(A) –2
(B) –1
(C) 0
(D) 1
(E) 2
[Reveal] Spoiler: OA

Kudos [?]: 74 [0], given: 15

Expert Post
5 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 41875

Kudos [?]: 128459 [5], given: 12173

Re: If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 21 Nov 2013, 03:42
5
This post received
KUDOS
Expert's post
smartyman wrote:
If 0 < x ≤ 1, then which one of the following is the maximum value of (x – 1)^2 + x ?

(A) –2
(B) –1
(C) 0
(D) 1
(E) 2


If you cannot spot that the maximum value of (x – 1)^2 + x for 0 < x ≤ 1 is when x=1 --> (x – 1)^2 + x = 1 you can do the following:

Since 0 < x ≤ 1, then (x – 1)^2 + x is positive --> discard A, B and C.

For the same reason: (x – 1)^2 is a non-negative fraction less than 1.

Thus (x – 1)^2 + x = (non-negative fraction less than 1) + (0 < x ≤ 1) < 2. Discard E.

Only D is left.

Answer: D.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Kudos [?]: 128459 [5], given: 12173

1 KUDOS received
Verbal Forum Moderator
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 627

Kudos [?]: 1355 [1], given: 136

Premium Member
Re: If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 21 Nov 2013, 03:42
1
This post received
KUDOS
smartyman wrote:
If 0 < x ≤ 1, then which one of the following is the maximum value of (x – 1)^2 + x ?

(A) –2
(B) –1
(C) 0
(D) 1
(E) 2


As x is a positive entity, the sum of the given expression can never be negative or zero.Eliminate all except D and E.

There are many ways to ascertain the maximum value now.

For example,
The given expression results as\(x^2-x+1 \to x(x-1)+1\)

For x=1, we have the sum as 1

For 0< x<1, we have the expression as : 1-(a negative quantity)

Thus, maximum value is for x=1.

D.
_________________

All that is equal and not-Deep Dive In-equality

Hit and Trial for Integral Solutions

Kudos [?]: 1355 [1], given: 136

Manager
Manager
User avatar
Joined: 22 Feb 2009
Posts: 214

Kudos [?]: 173 [0], given: 148

GMAT ToolKit User
Re: If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 27 Jul 2014, 14:49
Bunuel wrote:
smartyman wrote:
If 0 < x ≤ 1, then which one of the following is the maximum value of (x – 1)^2 + x ?

(A) –2
(B) –1
(C) 0
(D) 1
(E) 2


If you cannot spot that the maximum value of (x – 1)^2 + x for 0 < x ≤ 1 is when x=1 --> (x – 1)^2 + x = 1 you can do the following:

Since 0 < x ≤ 1, then (x – 1)^2 + x is positive --> discard A, B and C.

For the same reason: (x – 1)^2 is a non-negative fraction less than 1.

Thus (x – 1)^2 + x = (non-negative fraction less than 1) + (0 < x ≤ 1) < 2. Discard E.

Only D is left.

Answer: D.


I like the way you discard E. Thanks. +1 kudos
_________________

.........................................................................
+1 Kudos please, if you like my post

Kudos [?]: 173 [0], given: 148

1 KUDOS received
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1853

Kudos [?]: 2612 [1], given: 193

Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 31 Jul 2014, 00:49
1
This post received
KUDOS
Given that 0 < x ≤ 1

Placing value of x = 1 in the above equation:

\((1-1)^2 + 1 = 1\)

Answer = D
_________________

Kindly press "+1 Kudos" to appreciate :)

Kudos [?]: 2612 [1], given: 193

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16795

Kudos [?]: 273 [0], given: 0

Premium Member
Re: If 0 < x ≤ 1, then which one of the following is the maximum [#permalink]

Show Tags

New post 26 Sep 2017, 03:35
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Kudos [?]: 273 [0], given: 0

Re: If 0 < x ≤ 1, then which one of the following is the maximum   [#permalink] 26 Sep 2017, 03:35
Display posts from previous: Sort by

If 0 < x ≤ 1, then which one of the following is the maximum

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.