Check whether the following pair of statements are negation of each other. Give reason for your answer.
(i) a+b = b + a is true for every real number a and b.
(ii) There exists real numbers a and b for which a+b = b + a.
The negation of the statement
a+ b = b + a is true for every real number a and b.
There exist real numbers a and b for which a+b≠b+a.
So, the given statement is not the negation of the first statement.