Last visit was: 17 Dec 2024, 21:46 It is currently 17 Dec 2024, 21:46
Decision Tracker
My Rewards
New comers' posts
New posts
Unanswered

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.

Go to My Error Log Learn more
Close

Request Expert Reply

Confirm Cancel
PREVIOUS TOPIC
NEXT TOPIC

If it is true that

 1   2   
Tags :
Find Similar Topics  About  Add a Tag

Show Tags
Hide Tags

User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
If it is true that [#permalink] New post   02 Aug 2021, 14:02
Expert Reply
00:00

Question Stats:

49% (01:03) correct 50% (01:07) wrong based on 63 sessions

Hide Show timer Statistics

If it is true that \(m^2<9\) and \(m>-1\), which of the following must be true ??

A. \(m>-3\)

B. \(m>1\)

C. \(m>3\)

D. \(m<1\)

E. None of the abobe
ShowHide Answer
Official Answer
A
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [1]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
If it is true that [#permalink] New post   02 Aug 2021, 16:19
1
\((m-3)(m+3)<0\) ---> (I) m<3 and m>-3, (II) m>3 and m<-3. Accept (I) and Reject (II)
m>-1 AND -3<m<3 ---> -1<m<3. Answer must be within (-1, 3). Answer is E
Options given
A. (-3, ∞)
B. (1, ∞)
C. (3, ∞)
D. (- ∞, 1)
E. Correct answer
avatar
S
void
Senior Manager
Senior Manager
Joined: 03 Dec 2020
Posts: 440
Own Kudos [?]: 61 [0]
Given Kudos: 68
Send PM
Re: If it is true that [#permalink] New post   03 Aug 2021, 05:03
hello expert, assist on this problem what do after talking square root on both side.
m<(+3)(-3)
-3<m<3. how to reach conclusion for option A.
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [2]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   03 Aug 2021, 05:52
2
Expert Reply
\(m < +-3\)

\(-3<m<3\)

\(m<-1\) is redundant Is there to trick you

Only A must be true

30 seconds approach
avatar
S
COolguy101
Senior Manager
Senior Manager
Joined: 23 Jan 2021
Posts: 294
Own Kudos [?]: 172 [0]
Given Kudos: 81
Concentration: , International Business
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 04:51
motion2020 wrote:
\((m-3)(m+3)<0\) ---> (I) m<3 and m>-3, (II) m>3 and m<-3. Accept (I) and Reject (II)
m>-1 AND -3<m<3 ---> -1<m<3. Answer must be within (-1, 3). Answer is E
Options given
A. (-3, ∞)
B. (1, ∞)
C. (3, ∞)
D. (- ∞, 1)
E. Correct answer



Sir, I am confused in this highlighted part. Would you mind helping me?
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [1]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
If it is true that [#permalink] New post   Updated on: 13 Aug 2021, 09:54
1
IMO answer must be E
COolguy101 wrote:
motion2020 wrote:
\((m-3)(m+3)<0\) ---> (I) m<3 and m>-3, (II) m>3 and m<-3. Accept (I) and Reject (II)
m>-1 AND -3<m<3 ---> -1<m<3. Answer must be within (-1, 3). Answer is E
Options given
A. (-3, ∞)
B. (1, ∞)
C. (3, ∞)
D. (- ∞, 1)
E. Correct answer



Sir, I am confused in this highlighted part. Would you mind helping me?

Originally posted by motion2020 on 13 Aug 2021, 05:24.
Last edited by motion2020 on 13 Aug 2021, 09:54, edited 1 time in total.
avatar
S
COolguy101
Senior Manager
Senior Manager
Joined: 23 Jan 2021
Posts: 294
Own Kudos [?]: 172 [1]
Given Kudos: 81
Concentration: , International Business
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 05:28
1
motion2020 wrote:
IMO answer must be E
COolguy101 wrote:
motion2020 wrote:
\((m-3)(m+3)<0\) ---> (I) m<3 and m>-3, (II) m>3 and m<-3. Accept (I) and Reject (II)
m>-1 AND -3<m<3 ---> -1<m<3. Answer must be within (-1, 3). Answer is E
Options given
A. (-3, ∞)
B. (1, ∞)
C. (3, ∞)
D. (- ∞, 1)
E. Correct answer



Sir, I am confused in this highlighted part. Would you mind helping me?



Thank you very much sir for your swift response.
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 05:48
Expert Reply
The answer is A cannot be E
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [1]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
If it is true that [#permalink] New post   13 Aug 2021, 06:23
1
Carcass wrote:
The answer is A cannot be E

if answer is A and \(m>-3\) must be true, then \(m^2<9\) must not be true, for all cases of \(m>-3\)
\(m>-3\) implies all values of m to the right of the negative 3
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 08:36
Expert Reply
-3<m<3

Thi sis a must be true question and not could

C is m>3 so it is out immediately

B is m > 1 but we do know that m could be also 0 so is a could be true

D is m<1 and could be true but rules out the possibility to take into account values such as 2

A is m >-3 cover all our entire range.

My reasoning is that :)
avatar
B
koala
Manager
Manager
Joined: 18 Jan 2021
Posts: 81
Own Kudos [?]: 20 [1]
Given Kudos: 103
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 08:47
1
Carcass wrote:
\(m < +-3\)

\(-3<m<3\)

\(m<-1\) is redundant Is there to trick you

Only A must be true

30 seconds approach

If we select option A which is m > -3 then it also counts the possibility of m being equal to 3 or any other integer greater than that. Then this would contradict the statement mentioned in the question (i.e. m^2 < 9).
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
If it is true that [#permalink] New post   13 Aug 2021, 08:55
Expert Reply
koala wrote:
Carcass wrote:
\(m < +-3\)

\(-3<m<3\)

\(m<-1\) is redundant Is there to trick you

Only A must be true

30 seconds approach

If we select option A which is m > -3 then it also counts the possibility of m being equal to 3 or any other integer greater than that. Then this would contradict the statement mentioned in the question (i.e. m^2 < 9).


That's is also true. clever observation. from -3 to infinite

However, the meaning of the question is : which one among the answer choices is " amust be true" regardless

:)
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [0]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 09:07
\(m^2<9\) and \(m>-1\) imply \(-3<m<3\) and \(m>-1\). This is only possible, if one takes on both intervals.

answer A \(m>-3\) is true for \(m>-1\), and it's true on the interval \(-3<m<3\), but it's not true for the interval as defined in the answer choice A itself \(m>-3\). It must be true implies true at all times.


Carcass wrote:
If it is true that \(m^2<9\) and \(m>-1\), which of the following must be true ??

A. \(m>-3\)

B. \(m>1\)

C. \(m>3\)

D. \(m<1\)

E. None of the abobe
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 09:13
Expert Reply
ok ok guys

sorry. It is not the end.

It is just a discussion around a question :)


Simple is that
User avatar
D
rx10
Retired Moderator
Joined: 02 Dec 2020
Posts: 1831
Own Kudos [?]: 2148 [1]
Given Kudos: 140
GRE 1: Q168 V157

GRE 2: Q167 V161
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 09:18
1
Hi,

\(m^2<9\) & \(m>-1\)

So,
\(-3<m<3\) & \(m>-1\)

When we combine both these inequalities, we will get

\(-1 < m < 3\)

So in every case \(m\) will be greater than \(-3\)

Hence, answer A

motion2020 wrote:
\(m^2<9\) and \(m>-1\) imply \(-3<m<3\) and \(m>-1\). This is only possible, if one takes on both intervals.

answer A \(m>-3\) is true for \(m>-1\), and it's true on the interval \(-3<m<3\), but it's not true for the interval as defined in the answer choice A itself \(m>-3\). It must be true implies true at all times.
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 09:26
Expert Reply
:lol: :D Here we go. Join the army
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [0]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
If it is true that [#permalink] New post   13 Aug 2021, 09:48
IF it is true that -1<m<3, THEN which of the following must be true

A. m>−3, IF A is FALSE, THEN m is not greater than -3. A is NOT FALSE, because m is greater than -3

B. m>1, IF B is FALSE, THEN m is not greater than 1. B is FALSE, because m can be -0.5 or 0; m is not greater than 1.

C. m>3, IF C is FALSE, THEN m is not greater than 3. C is FALSE, because m cannot be 3 and it's not greater than 3.

D. m<1, IF D is FALSE, THEN m is not less than 1. D is FALSE, because m can be 2 or 2.5; m is not less than 1.

E. ..

this is called proof by contradiction, and answer is indeed A
User avatar
D
Carcass
Verbal Expert
Joined: 18 Apr 2015
Posts: 30349
Own Kudos [?]: 36746 [0]
Given Kudos: 26080
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 09:59
Expert Reply
motion2020 wrote:
IF it is true that -1<m<3, THEN which of the following must be true

A. m>−3, IF A is FALSE, THEN m is not greater than -3. A is NOT FALSE, because m is greater than -3

B. m>1, IF B is FALSE, THEN m is not greater than 1. B is FALSE, because m can be -0.5 or 0; m is not greater than 1.

C. m>3, IF C is FALSE, THEN m is not greater than 3. C is FALSE, because m cannot be 3 and it's not greater than 3.

D. m<1, IF D is FALSE, THEN m is not less than 1. D is FALSE, because m can be 2 or 2.5; m is not less than 1.

E. ..

this is called proof by contradiction, and answer is indeed A



sorry if I am wrong but the post with the paper attached was not E...minutes ago ??? :-o
User avatar
G
motion2020
Retired Moderator
Joined: 19 Nov 2020
Posts: 326
Own Kudos [?]: 377 [0]
Given Kudos: 64
GRE 1: Q160 V152
Send PM
Re: If it is true that [#permalink] New post   13 Aug 2021, 10:19
It was repeated from the above solution lol. I managed to check If/Then statement for this question. Thanks for your original post. This question is quite didactic ☺️ another vocab entry popes out of my mind
Carcass wrote:
motion2020 wrote:
IF it is true that -1<m<3, THEN which of the following must be true

A. m>−3, IF A is FALSE, THEN m is not greater than -3. A is NOT FALSE, because m is greater than -3

B. m>1, IF B is FALSE, THEN m is not greater than 1. B is FALSE, because m can be -0.5 or 0; m is not greater than 1.

C. m>3, IF C is FALSE, THEN m is not greater than 3. C is FALSE, because m cannot be 3 and it's not greater than 3.

D. m<1, IF D is FALSE, THEN m is not less than 1. D is FALSE, because m can be 2 or 2.5; m is not less than 1.

E. ..

this is called proof by contradiction, and answer is indeed A



sorry if I am wrong but the post with the paper attached was not E...minutes ago ??? :-o


Posted from my mobile device
avatar
B
ademeutia
Manager
Manager
Joined: 23 Mar 2022
Posts: 62
Own Kudos [?]: 24 [1]
Given Kudos: 26
Send PM
Re: If it is true that [#permalink] New post   11 Apr 2022, 22:36
1
m^2 < 9
divided by 3 ==> m < 3
divided by (-3) ==> m > -3
Prep Club for GRE Bot
gmatclubot
Re: If it is true that [#permalink]
11 Apr 2022, 22:36
 1   2   
Moderators:
adewale223
GRE Instructor
88 posts
bronaugust
GRE Forum Moderator
37 posts
BrushMyQuant
Moderator
1115 posts
VibhuAnurag
GRE Instructor
234 posts

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

Main navigation

Partners

GRE Resources

www.ets.org/gre | About | Terms and Conditions and Privacy Policy | Prep Club for GRE Rules | Contact