The Gateway to Computer Science Excellence
For all GATE CSE Questions
Toggle navigation
GATE Overflow
Facebook Login
Google Login
or
Email or Username
Password
Remember
Login
Register

I forgot my password
All Activity
Questions
Unanswered
Tags
Subjects
Users
Ask
Previous
Blogs
New Blog
Exams
First time here? Checkout the
FAQ
!
x
×
Close
Use the google search bar on side panel. It searches through all previous GATE/other questions. For hardcopy of previous year questions please see
here
ME Test Series:Propositinal Logic
0
votes
243
views
madeeasytestseries
mathematicallogic
asked
Dec 16, 2016
in
Mathematical Logic
by
KISHALAY DAS
Loyal
(
6.5k
points)
retagged
Jun 4, 2017
by
Arjun

243
views
Facebook
Google+
Twitter
answer
comment
+1
All are invalid
0
Please explain why
0
@arjun sir,pls help in this one.
+4
sorry, I dont want to boil my brain solving such questions. For mathematical logic there are numerous previous year questions and also many PDFs are given in gatecse. When all those are there I do not want to waste time decoding such poorly formatted questions.
0
i understand arjun sir,but if u colud just tell which option is correct then that would have helped..!
thanks anyway :)
+3
^That means you did not understand :(
Please
log in
or
register
to add a comment.
Please
log in
or
register
to answer this question.
1
Answer
+1
vote
Statement 1)
Let the domain be set of real numbers.
B: true
A: number is integer
LHS = false and RHS= true
So, fale double implies true is false.
Statement 2)
Let the domain be set of real numbers.
B: false
A: number is integer
LHS = true and RHS= false
So, true double implies false is false.
answered
Dec 23, 2016
by
Sushant Gokhale
Boss
(
18.1k
points)
comment
Show 13 previous comments
0
Just notice the difference here:
Vx B > A(x)
and
Vx B > Vx A(x)
did you get it?
0
@Akriti. Try this.
https://gateoverflow.in/63850/propositionallogicselfdoubt
0
@sushant,yes,i have gone through the above link and see in that one 3rd statment is true.
meanwhile i understood that statement 1 is incorrect but
for statement 2,i was thinking that as B is already true then whether it is for some A to be true or for all A to be true,it is true afterall as it is universal.i guess i am wrong only.:(
THanks for helping out!
3rd statment is wrong na??
0
Lhs
= $\exists$x( A(x) > B(x) )
= $\exists$x( ~A(x) V B(x) )
= $\exists$x ~A(x) V $\exists$x B(x)
= Vx A(x) V $\exists$x B(x)
= RHS
So, true.
0
Also try using example.
0
thanks sushant,
if i take one example,we take domain as {3,6,9}
A=div by 2 and B = div by 3
then RHS is obviously TRue but what about LHS ∃x( A(x) > B(x) ) as here,A is not true for anyone.so LHS is true or false/?
0
x=6, A is true and B is true. So, LHS=true
0
sorry,domain is {3,9,15},,then tell for LHS.
0
Yes, u got it :)
0
thanks sushant..:)
Please
log in
or
register
to add a comment.
← Prev. Qn. in Sub.
Next Qn. in Sub. →
← Prev.
Next →
Related questions
0
votes
1
answer
1
Logic
What is the correct translation of the following statement into mathematical logic? “If everyone respect somebody then that person is honest” Here respect (a, b) represent a respect b. None of these I feel it should be a but the answer is b
asked
Jan 25, 2017
in
Mathematical Logic
by
Pankaj Joshi
Active
(
3k
points)

126
views
mathematicallogic
madeeasytestseries
0
votes
1
answer
2
mathematical logic
asked
Jan 20, 2017
in
Mathematical Logic
by
vaishali jhalani
Loyal
(
5.8k
points)

82
views
mathematicallogic
madeeasytestseries
+1
vote
0
answers
3
Made Easy test
Which of the following option is correct for the given predicate with domain of all people Where F(x, y) means x is a friend of y'. If two persons are not friend of each other then they have atleast one friend common. If two persons have atleast one ... above I think the answer should be there exists a person all of his friends are not friends with each other but the solution says b
asked
Feb 1, 2017
in
Mathematical Logic
by
Pankaj Joshi
Active
(
3k
points)

66
views
mathematicallogic
madeeasytestseries
Quick search syntax
tags
tag:apple
author
user:martin
title
title:apple
content
content:apple
exclude
tag:apple
force match
+apple
views
views:100
score
score:10
answers
answers:2
is accepted
isaccepted:true
is closed
isclosed:true
Recent Posts
BARC Interview Experience 15th June 2018
COAP Admission and IITD, IITK Interview Experience 2018
MS Interview Experience at IITK
Effect of Academic/ Career Gap during Mtech Placements at IIT/NIT
Gate Rank Improvement
All categories
General Aptitude
1.3k
Engineering Mathematics
5.2k
Discrete Mathematics
3.6k
Mathematical Logic
1.4k
Set Theory & Algebra
924
Combinatory
634
Graph Theory
600
Probability
651
Linear Algebra
527
Calculus
387
Digital Logic
2k
Programming & DS
3.7k
Algorithms
3.2k
Theory of Computation
4k
Compiler Design
1.6k
Operating System
2.8k
Databases
3k
CO & Architecture
2.6k
Computer Networks
3k
Non GATE
1k
Others
1.3k
Admissions
484
Exam Queries
434
Tier 1 Placement Questions
17
Job Queries
56
Projects
8
Follow @csegate
Gatecse
Recent Blog Comments
thanks for the info .but qstn 1.4 time complexity ...
What was your GATE rank and score this time ...
finish all subjects first then start taking all ...
@Arjun sir Address Confirmation mail not ...
Those who pay till today  June 17 can expect the ...
36,075
questions
43,521
answers
123,662
comments
42,747
users