Last visit was: 26 Apr 2024, 15:29 It is currently 26 Apr 2024, 15:29

Close

GRE Prep 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 GRE 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
Verbal Expert
Joined: 18 Apr 2015
Posts: 28642
Own Kudos [?]: 33131 [2]
Given Kudos: 25178
Send PM
avatar
Manager
Manager
Joined: 04 Feb 2019
Posts: 204
Own Kudos [?]: 412 [1]
Given Kudos: 0
Send PM
Intern
Intern
Joined: 03 Sep 2020
Posts: 23
Own Kudos [?]: 5 [2]
Given Kudos: 13
Send PM
Verbal Expert
Joined: 18 Apr 2015
Posts: 28642
Own Kudos [?]: 33131 [1]
Given Kudos: 25178
Send PM
Re: If (x – y)3 > (x – y)2, then which one of the following must [#permalink]
1
Expert Reply
tavishg wrote:
Hi Carcass
How do I prove C and D wrong?


That's is a very good question.

I think you are thinking to pick up numbers and test the answer choices. Working on them which is true and which is not. I understood what you mean. However, the best way is to manipulate the stem and thinking logically

Now, \((x – y)^3 > (x – y)^2\)

the LHS is positive because squared

So we can divide both for the LHS and we will end up with

x-y>1

x > 1+y

So x is > of y (some number) +1

So x>y and ONLY x^3>y^3

The other options such as D could not be true or yes

Proving C and D are wrong is too cumbersome in a classic way

I hope I satisfied your question
Manager
Manager
Joined: 02 Sep 2019
Posts: 181
Own Kudos [?]: 142 [1]
Given Kudos: 94
Concentration: Finance
GRE 1: Q151 V148
GPA: 3.14
Send PM
Re: If (x – y)3 > (x – y)2, then which one of the following must [#permalink]
1
This is really confusing.
We assume that x & y are negative
x=-2 and y=-4
(-2-(-4)^3> (-2-(-4)^2
in this case only E fits here
(E) x^3 > y^3
(-2)^3 > (-4)^3
User avatar
GRE Prep Club Legend
GRE Prep Club Legend
Joined: 07 Jan 2021
Posts: 4431
Own Kudos [?]: 68 [0]
Given Kudos: 0
Send PM
Re: If (x y)3 > (x y)2, then which one of the following must [#permalink]
Hello from the GRE Prep Club BumpBot!

Thanks to another GRE Prep 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.
Prep Club for GRE Bot
[#permalink]
Moderators:
Moderator
1085 posts
GRE Instructor
218 posts

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