The solitary root number 3 is a mathematical concept, which means that it is an irrational number and there is no rational number equal to it. The root number 3 is an infinite cycle decimal, and the number 1 and the number 7 appear infinitely continuously after the decimal point. That is,/kloc-0 1.7320807577778+0669485 Because the root number 3 is irrational, it cannot be expressed as any finite or repeated decimal or fraction, but only as an infinite decimal or approximation. Therefore, the root number 3 is a unique and lonely mathematical entity.