# maths

posted by .

explain why are the following not groups:

1)the set of Z integers with operation subtraction
2)The set of Z integers with operation addition
3)The set of R* of all non zero real numbers with addition

## Similar Questions

1. ### math

I do not undeerstand this question for homework. Determine if the set is closed for the given operation. 1. yes or no- The set of positive fractions for division. 2. yes or no=The set of positive integers for subtraction. Can someone …
2. ### math

I do not undeerstand this question for homework. Determine if the set is closed for the given operation. 1. yes or no- The set of positive fractions for division. 2. yes or no=The set of positive integers for subtraction. Can someone …
3. ### Math

The operation § associated to any number means “divide the number by 3”. Is the set of integers paired with the operation § a mathematical system?
4. ### Maths

A give an example of a function whose domain equals the set of real numbers and whose range equals the set?

Please check urgently .I have to submit the assignment A give an example of a function whose domain equals the set of real numbers and whose range equals the set?

Please check urgently .I have to submit the assignment A give an example of a function whose domain equals the set of real numbers and whose range equals the set?
7. ### SAT prep help

Set M consists of the consecutive integers from -15 to y, inclusive. If the sum of all the integers in set M is 70, How many numbers are in the set?
8. ### SAT math

Set M consists of the consecutive integers from -15 to y, inclusive. If the sum of all the integers in set M is 70, How many numbers are in the set?
9. ### Math

1. Set I contains six consecutive integers. Set J contains all integers that result from adding 3 to each of the integers in set I and also contains all integers that result from subtracting 3 from each of the integers in set I. How …
10. ### Algebra I

Tell whether the set is closed under the operation. If it is not closed give an example that shows that the set is not closed under the operation. 10. Positive irrational numbers; division 11. Negative rational numbers; multiplication …

More Similar Questions