(i) Let
And, so
Therefore, andare two irrational numbers and their difference is a rational number
(ii) Let are two irrational numbers and their difference is an irrational number
Because is an irrational number
(iii) Let are two irrational numbers and their sum is a rational number
That is
(iv) Let are two irrational numbers and their sum is an irrational number
That is
(v) Let are two irrational numbers and their product is a rational number
That is
(vi) Let are two irrational numbers and their product is an irrational number
That is
(vii) Let are two irrational numbers and their quotient is a rational number
That is
(viii) Let are two irrational numbers and their quotient is an irrational number
That is