ELI5: Explain Like I'm 5

Routh–Hurwitz theorem

Imagine you have a bunch of numbers and you want to know if they will make a big mess or if they will behave nicely. The Routh-Hurwitz theorem helps you figure that out.

To use the theorem, you need to make a special kind of table with the numbers. It's like a game board where you put the numbers in rows and columns.

Then, you do some math with the numbers to fill in the rest of the table. You take some pairs of numbers and subtract them, then divide by another number. This gives you a new number that you write in a new row of the table.

You do this over and over again until you have filled in the whole table. Then, you look at the pattern of the numbers in the first column.

If all the numbers in the first column are positive, then the original bunch of numbers will behave nicely and not make a mess. But if any of the numbers in the first column are zero or negative, then things could get messy and you need to be careful.

So basically, the Routh-Hurwitz theorem helps you predict whether a system (like an electrical circuit or a control system) will be stable (well-behaved) or unstable (messy and unpredictable).