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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Re: DS-integers,,,,, [#permalink]
06 Aug 2005, 05:05

(A) for me.

In statement 2, x or y may be negative. Consider x,y,z=-10,-9,-20 and x,y,x=2,1,1. You will get different results.

In (1), the value of x^2, y^2 and z^2 must be +ve and if the sum of x^2 and y^2 is greater than z^2, then we can conclude that the same will hold true for the stem.

And you would never write all that out in the test itself.

The point is that even with x,y>0, there are terms with positive and negative signs involving powers of x and y on the right. So that makes it quite likely there are two different cases.

Re: DS-integers,,,,, [#permalink]
09 Aug 2005, 20:54

1. x^2 + y^2 > z^2
(x^2+y^2)^2>z^4
x^4+y^4+2x^2y^2>z^4
x^4+y^4>z^4-2x^2y^2
Since x^2y^2>0, we don't know if x^4+y^4>z^4.
Insufficient

2. x + y > z
They could be different signs. Say both x and y are small positive numbers and z is a large negative. Then x^4+y^4 could be smaller than z^4. But the opposite is also possible. So insufficient.

Combined:
Not very easy to prove. The best way to go, in my opinion is by counter examples. As long as you can find a set of numbers where both 1 and 2 are satisfied to answer No to the stem then you are all set. Because it is easy to find examples to say Yes to the stem, finding the No answer would mean the answer is not unique and that 1 and 2 combined are not sufficient.
Anyways you could try with the closest numbers such as 3, 3, 4, where 3+3>4, 3^2+3^2>4^2, but 3^4+3^4<4^4.

Therefore the answer is E. _________________

Keep on asking, and it will be given you;
keep on seeking, and you will find;
keep on knocking, and it will be opened to you.

gmatclubot

Re: DS-integers,,,,,
[#permalink]
09 Aug 2005, 20:54

Originally posted on MIT Sloan School of Management : We are busy putting the final touches on our application. We plan to have it go live by July 15...