How can we use irrational numbers in math if we don’t know the full number?

Question

How can we use irrational numbers in math if we don’t know the full number?

In: 232

Answer 1

By this logic, we don’t know the full number of 1/7 either. It has an infinite decimal expansion, it goes on forever. But we can calculate it to whatever precision we want because we know the pattern.

This is how we use irrational numbers. The patterns are a bit more complicated, but we still have formulas or algorithms to approximate the value of these numbers as closely as we want to get it.