My Math Forum Quick question on Sets?

 Applied Math Applied Math Forum

 August 25th, 2013, 08:25 AM #1 Newbie   Joined: Jul 2013 Posts: 18 Thanks: 0 Quick question on Sets? Given the set J={(x , y): x?? , y?? , 2x?y=4} , and the set K={( x , y): x?? , y?? , x?2y=1} what does the set J?K represent? does J?K represent the factors of 4?
August 25th, 2013, 09:17 AM   #2
Global Moderator

Joined: Nov 2006
From: UTC -5

Posts: 16,046
Thanks: 938

Math Focus: Number theory, computational mathematics, combinatorics, FOM, symbolic logic, TCS, algorithms
Re: Quick question on Sets?

Quote:
 Originally Posted by maths4computing does J?K represent the factors of 4?
J and K are sets of pairs, so their intersection will also be a set of pairs.

Mechanically, you can write
J?K = {(x , y): x?? , y?? , 2x?y=4 and x?2y=1}
but you should simplify this.

August 25th, 2013, 12:26 PM   #3
Math Team

Joined: Dec 2006
From: Lexington, MA

Posts: 3,267
Thanks: 408

Re: Quick question on Sets?

Hello, maths4computing!

Quote:
 $\text{Given the set: }\:J\:=\:\{\,(x,\,y)\,:\, x\in R,\;y\in R,\;2x\,-\,y\:=\:4\,\} \;\;\;\text{and the set: }\:K\:=\:\{\,(x,\,y)\,:\,x\,\in\,R,\;y\,\in\,R,\; x\,-\,2y\:=\:1\,\} \text{What does the set }J\,\cap\,K\text{ represent?}$

$\,J\text{ is the set of points on the straight line: }\:2x\,-\,y \:=\:4
K\text{ is the set of points on the straight line: }\:x\,-\,2y\:=\:1$

$J\,\cap\,K\text{ is the intersection of the two lines.}$

$\text{Got it?}$

August 25th, 2013, 12:30 PM   #4
Newbie

Joined: Jul 2013

Posts: 18
Thanks: 0

Re: Quick question on Sets?

Quote:
Originally Posted by soroban
Hello, maths4computing!

Quote:
 $\text{Given the set: }\:J\:=\:\{\,(x,\,y)\,:\, x\in R,\;y\in R,\;2x\,-\,y\:=\:4\,\} \;\;\;\text{and the set: }\:K\:=\:\{\,(x,\,y)\,:\,x\,\in\,R,\;y\,\in\,R,\; x\,-\,2y\:=\:1\,\} \text{What does the set }J\,\cap\,K\text{ represent?}$

$\,J\text{ is the set of points on the straight line: }\:2x\,-\,y \:=\:4
K\text{ is the set of points on the straight line: }\
\,-\,2y\:=\:1" />

$J\,\cap\,K\text{ is the intersection of the two lines.}$

$\text{Got it?}$

I understand, thanks again

 Tags question, quick, sets

 Thread Tools Display Modes Linear Mode

 Similar Threads Thread Thread Starter Forum Replies Last Post Timk Algebra 3 March 27th, 2012 10:31 PM schLoL Algebra 5 April 26th, 2011 03:36 PM seecs Algebra 1 November 10th, 2010 01:10 PM eric3353 Calculus 1 August 13th, 2008 12:51 PM axelle Economics 1 May 17th, 2008 10:44 PM

 Contact - Home - Forums - Cryptocurrency Forum - Top