Proof that π is irrational
It's really hard to explain this to a 5 year old, but here goes! Let's start with a number. A number is something like 3, 5 or 7; any number you can think of. Now, what π (or "pi") is, is a special number that we use a lot in math and science; it's kind of like a special number that isn't quite like any other number. Anyway, π is a special number that looks like this: 3.1415926535897932384626433832795
The tricky thing about π is that it's an "irrational" number. That means that it can't be written as a "fraction" - which is two numbers that are divided by each other. For example, if we wanted to write the number 2 as a fraction, then we could write it like this: 2/1. That's a fraction! A number like 3 can also be written as a fraction like this: 3/1.
But π can't be written as a fraction, not matter how hard you try. That's because it's an irrational number. That's why it's special!
The tricky thing about π is that it's an "irrational" number. That means that it can't be written as a "fraction" - which is two numbers that are divided by each other. For example, if we wanted to write the number 2 as a fraction, then we could write it like this: 2/1. That's a fraction! A number like 3 can also be written as a fraction like this: 3/1.
But π can't be written as a fraction, not matter how hard you try. That's because it's an irrational number. That's why it's special!