Events & Promotions
|
|
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Nov 2007:30 AM PST
-08:30 AM PST
Learn what truly sets the UC Riverside MBA apart and how it helps in your professional growth
Nov 2001:30 PM EST
-02:30 PM IST
Learn how Kamakshi achieved a GMAT 675 with an impressive 96th %ile in Data Insights. Discover the unique methods and exam strategies that helped her excel in DI along with other sections for a balanced and high score.
Nov 2206:30 AM PST
-08:30 AM PST
Let’s dive deep into advanced CR to ace GMAT Focus! Join this webinar to unlock the secrets to conquering Boldface and Paradox questions with expert insights and strategies. Elevate your skills and boost your GMAT Verbal Score now!
Nov 2211:00 AM IST
-01:00 PM IST
Do RC/MSR passages scare you? e-GMAT is conducting a masterclass to help you learn – Learn effective reading strategies Tackle difficult RC & MSR with confidence Excel in timed test environment- Nov 23
11:00 AM IST
-01:00 PM IST
Attend this free GMAT Algebra Webinar and learn how to master the most challenging Inequalities and Absolute Value problems with ease. 
Nov 2407:00 PM PST
-08:00 PM PST
Full-length FE mock with insightful analytics, weakness diagnosis, and video explanations!
Nov 2510:00 AM EST
-11:00 AM EST
Prefer video-based learning? The Target Test Prep OnDemand course is a one-of-a-kind video masterclass featuring 400 hours of lecture-style teaching by Scott Woodbury-Stewart, founder of Target Test Prep and one of the most accomplished GMAT instructors.
11 Sep 2007, 01:32
Kudos
Bookmarks
N
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!
Difficulty:
(N/A)
Question Stats:
100% (00:00) correct
0%
(00:00)
wrong
based on 19
sessions
History
Date
Time
Result
Not Attempted Yet
How many roots does the following equation have?
sqrt(x^2 + 1) + sqrt(x^2 + 2) = 2
a) 0
b) 1
c) 2
d) 3
e) 4
I started w/ squaring both sides to get:
2 sqrt(x^4+3x^2+2) = -(2x^2+1)
Then I squared both sides once again to arrive at:
8x^4+16x^2+9 = 0
Since the highest power of x=4, I thought that the equation shud have 4 roots, hence answer e. But I'm wrong. Where did I go wrong/ what's a better way to solve this? Thanks.
sqrt(x^2 + 1) + sqrt(x^2 + 2) = 2
a) 0
b) 1
c) 2
d) 3
e) 4
I started w/ squaring both sides to get:
2 sqrt(x^4+3x^2+2) = -(2x^2+1)
Then I squared both sides once again to arrive at:
8x^4+16x^2+9 = 0
Since the highest power of x=4, I thought that the equation shud have 4 roots, hence answer e. But I'm wrong. Where did I go wrong/ what's a better way to solve this? Thanks.
Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Data Sufficiency (DS) Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
12 Sep 2007, 01:50
Kudos
Bookmarks
sqrt(x^2 + 1) + sqrt(x^2 + 2) = 2
1. since sqrt(n) can never be less then zero.
2. and x^2 will always give positive value.
x^2 >= 0
sqrt(0^2 + 1) + sqrt(0^2 + 2) = 2
sqrt(1) + sqrt(2) = 2
~ 2.4 > 2 ---> has to be !
I think there are zero solutions for this equation (unless you can use i - irrational numbers)
1. since sqrt(n) can never be less then zero.
2. and x^2 will always give positive value.
x^2 >= 0
sqrt(0^2 + 1) + sqrt(0^2 + 2) = 2
sqrt(1) + sqrt(2) = 2
~ 2.4 > 2 ---> has to be !
I think there are zero solutions for this equation (unless you can use i - irrational numbers)
