Question

Tell whether the set is closed under the operation indicated.

If not closed, provide a counterexample.

1.) integers under addition                            2.) integers under division
 
3.) whole numbers under subtraction             4.) Irrational numbers under addition

Answer 1

Tell whether the set is closed under the operation indicated.If not closed, provide a counterexample.

1.) integers under addition 2.) integers under division

3.) whole numbers under subtraction 4.) Irrational numbers under addition

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