Answer:
(a) π + (-π) = 0
Explanation:
You want a counterexample for the statement that irrationals are closed under addition.
Closed set
A set is closed under addition if adding members of the set always results in a member of the set.
π + (-π) = 0
This shows that adding members of the set can result in a rational number. This is the counterexample you're looking for.
(1/2) + (-1/2) = 0
Irrelevant. 1/2 is rational, so is not a member of the set of irrationals.
π + π = 2π
An example of a sum that is an element of the set. This is not a counterexample.
(1/2) +(1/2) = 1
Irrelevant. 1/2 is rational, so is not a member of the set of irrationals.
<95141404393>