Addition under which any pair $$(a, b)$$ of irrational numbers is made to correspond to an irrational number $$(a + b)$$ called the sum of a and b.

Because an irrational number is expressed by an unlimited, non-repeating decimal sequence, we cannot express the sum of two irrational numbers in the form of a repeating decimal sequence.

### Examples

$$7+8\sqrt{5}-2\sqrt{5} -4=3+6\sqrt{5}$$

$$5+11\pi -3 +7\pi = (5-3)+(11\pi + 7\pi) = 2 +18\pi$$