Posted by b6 on Monday, January 21, 2013 at 4:12pm.
Which set of integers is not closed under what operation?
+

x
Division
I thought it was division but I don't understand , can you please explain this.
Thanks
 math  Reiny, Monday, January 21, 2013 at 5:16pm
Think of it this way:
If you add two integers, will you always get back an integer ? YES , so it is closed under addition
if you divide two integers will you always get back an integer.
e.g. 6 ÷ 4 = 1.5 , which is NOT an integer
so not closed under division
make a similar test for subtraction and multiplication.
What do you think?
 math  b6, Monday, January 21, 2013 at 5:21pm
6*4=24 it is an integer=closed for mult.
107=3 so it is also an integer
Thanks
Answer this Question
Related Questions
 Math Algebra  The natural numbers are closed under division. true or false? the...
 math  I do not undeerstand this question for homework. Determine if the set is ...
 math  I do not undeerstand this question for homework. Determine if the set is ...
 help me  under which operation is the set {1,0,1} closed? 1 multiplication 2 ...
 mathematics help me plz.....  under which operation is the set {1,0,1} closed...
 math  I am really confused about sets. Could you explain to me if the following...
 6TH GR. ALGEBRA  EXTENDING THE LESSON If you add any two rational numbers, the...
 math  Give a counterexample to show that each of the following generalizations ...
 math  explain whether each set is closed under the given operation {1,0,1}...
 math  What expression is a counterexample to the statement The whole numbers ...