GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 18 Aug 2018, 02:07

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

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: 58
If 0 < x ≤ 1, then which one of the following is the maximum  [#permalink]

Show Tags

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

Difficulty:

  15% (low)

Question Stats:

76% (01:10) correct 24% (00:49) wrong based on 238 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
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47978
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
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

General Discussion
Verbal Forum Moderator
User avatar
Joined: 10 Oct 2012
Posts: 615
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
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

Manager
Manager
User avatar
Joined: 22 Feb 2009
Posts: 189
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
1
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

SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1835
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
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 :)

Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 7751
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

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.