Find all School-related info fast with the new School-Specific MBA Forum

It is currently 01 Sep 2015, 12:22
GMAT Club Tests

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If root{3-2x} = root(2x) +1, then 4x^2 =

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Senior Manager
Senior Manager
avatar
Joined: 10 Nov 2010
Posts: 269
Location: India
Concentration: Strategy, Operations
GMAT 1: 520 Q42 V19
GMAT 2: 540 Q44 V21
WE: Information Technology (Computer Software)
Followers: 5

Kudos [?]: 131 [0], given: 22

If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 05 Apr 2011, 19:34
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

57% (02:15) correct 43% (02:19) wrong based on 74 sessions
If \(\sqrt{3-2x} = \sqrt{2x} +1\), then \(4x^2\) =

(A) 1
(B) 4
(C) 2 − 2x
(D) 4x − 2
(E) 6x − 1

OPEN DISCUSSION OF THIS QUESTION IS HERE: if-root-3-2x-root-2x-1-then-4x-135539.html

Official Guide 12 Question

GMAT Official Guide 12

Question: 16
Page: 22
Difficulty: 700

Find All Official Guide Questions

Video Explanations:
[Reveal] Spoiler: OA

_________________

The proof of understanding is the ability to explain it.

Kaplan GMAT Prep Discount CodesKnewton GMAT Discount CodesManhattan GMAT Discount Codes
Manager
Manager
avatar
Joined: 17 Jan 2011
Posts: 231
Followers: 1

Kudos [?]: 26 [0], given: 4

Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 05 Apr 2011, 20:26
=>(3-2x)^1/2=(2x)^1/2+1

Square both sides

=>(3-2x)=(2x)+1+2*(2x)^1/2

=>(2-4x)=2*(2x)^1/2

=>(1-2x)=(2x)^1/2

Square both sides again

1 - 4x + 4x^2 = 2x
4x^2=6x-1
So E.
_________________

Good Luck!!!

***Help and be helped!!!****

Manager
Manager
avatar
Joined: 17 Jan 2011
Posts: 231
Followers: 1

Kudos [?]: 26 [0], given: 4

Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 05 Apr 2011, 20:28
GMATD11 wrote:
16.) \sqrt{3-2x}=\sqrt{2x}+1 then 4x^2 =

a) 1
b) 4
c) 2-2x
d) 4x-2
e) 6x-1

Guys i solved and got 1

but OA is different .

I want to know the reason nd different approach that i need to follow.



Alternately, to verify your ans 4x^2 = 1 means x = 1/2
Substitute the value 1/2 in eq, it doesn't make LHS=RHS
_________________

Good Luck!!!

***Help and be helped!!!****

SVP
SVP
avatar
Joined: 16 Nov 2010
Posts: 1676
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 31

Kudos [?]: 374 [0], given: 36

Premium Member Reviews Badge
Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 05 Apr 2011, 21:34
root(3-2x) - root(2x) = 1

Squaring both sides :


3 - 2x + 2x - 2 * root(6x - 4x^2) = 1

=> -2 * root(6x - 4x^2) = -2

=> root(6x - 4x^2) = 1

Squaring again :

=> 6x - 4x^2 = 1

=> 4x^2 = 6x - 1


Answer - E
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

Director
Director
avatar
Joined: 01 Feb 2011
Posts: 759
Followers: 14

Kudos [?]: 75 [0], given: 42

Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 06 Apr 2011, 05:17
Squaring on both sides we have
2-4x = 2*sqrt(2x)
Squaring on both sides again we have
4x^2 = 6x-1

Answer E

Posted from my mobile device Image
Manager
Manager
avatar
Joined: 17 Jul 2013
Posts: 110
Followers: 0

Kudos [?]: 1 [0], given: 67

Premium Member
Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 21 Jun 2014, 00:33
Before proceeding with the solving part , give a look at the options provided. Since none of the options has under root involved in the answer choices think to eliminate that from the target answer.

If u keep the squareroot value on one side w/o making any equation will help us to solve.
squaring both sides and bringing the non squareroot values on the one side and keeping squareroot 2 on the other side .. squaring the terms on both sides ... will give answer ....

let me know in case of any query ...
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 29173
Followers: 4736

Kudos [?]: 50033 [0], given: 7519

Re: If root{3-2x} = root(2x) +1, then 4x^2 = [#permalink] New post 21 Jun 2014, 02:59
Expert's post
GMATD11 wrote:
If \(\sqrt{3-2x} = \sqrt{2x} +1\), then \(4x^2\) =

(A) 1
(B) 4
(C) 2 − 2x
(D) 4x − 2
(E) 6x − 1



If \(\sqrt{3-2x} = \sqrt{2x} +1\), then \(4x^2\) =

(A) 1
(B) 4
(C) 2 − 2x
(D) 4x − 2
(E) 6x − 1

\(\sqrt{3-2x} = \sqrt{2x} +1\) --> square both sides: \((\sqrt{3-2x})^2 =(\sqrt{2x} +1)^2\) --> \(3-2x=2x+2*\sqrt{2x}+1\) --> rearrange so that to have root at one side: \(2-4x=2*\sqrt{2x}\) --> reduce by 2: \(1-2x=\sqrt{2x}\) --> square again: \((1-2x)^2=(\sqrt{2x})^2\) --> \(1-4x+4x^2=2x\) --> rearrange again: \(4x^2=6x-1\).

Answer: E.

OPEN DISCUSSION OF THIS QUESTION IS HERE: if-root-3-2x-root-2x-1-then-4x-135539.html
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis ; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) ; 12. 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?
25 extra-hard Quant Tests

GMAT Club Premium Membership - big benefits and savings

Re: If root{3-2x} = root(2x) +1, then 4x^2 =   [#permalink] 21 Jun 2014, 02:59
    Similar topics Author Replies Last post
Similar
Topics:
5 Experts publish their posts in the topic If m=9^(x−1), then in terms of m, 3^(4x−2) goodyear2013 3 03 Jun 2014, 13:20
26 Experts publish their posts in the topic If root{3-2x} = root(2x) +1, then 4x^2 = Bunuel 24 09 Jul 2012, 02:23
8 Experts publish their posts in the topic If rot{3-2x} = root(2x) +1, then 4x^2 = tonebeeze 10 17 Jan 2011, 20:51
25 Experts publish their posts in the topic If x>0 then 1/[(root(2x)+root(x)]=? ajit257 22 14 Dec 2010, 18:08
12 Experts publish their posts in the topic If 27^(4x + 2) 162^-2x 36^x 9^(6 2x) = 1, then what is xALIx 13 10 Jul 2008, 18:05
Display posts from previous: Sort by

If root{3-2x} = root(2x) +1, then 4x^2 =

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.