Question

who explained a '0' is valuabe

Answer 1

Zero is a strange beast. It took until the 7th century for it to be explicitly recognized as a number in its own right, when the ancient Indians developed a numerical system that expressed zero with its own symbol. Since the development of this number system, which we still use today, zero has been instrumental in our exploration of mathematics.  

The human use of numbers sprang from the practical need to count things, but at the time zero was only used to denote an absence of value. In this light, could it even be considered a number? As human thought progressed, however, and mathematics became more of an abstract process to unravel reality, zero started to prove itself as a very useful tool.

This animated video from The Royal Institution, narrated by mathematician Hannah Fry, tells the story of this winding history, from its role in ancient civilizations to our current world of computer technology, and explains how zero became a mathematical hero.

I hope it can help....

Answer 2

I think you are confusing the mathematical word 'value' with the common English word 'value'. In day to day language, things of no value are, by definition, worthless. But in mathematics, the value of zero is different in different places. 

Mathematicians overload the term 0. There is a 0 matrix, 0 subspace, the real 0, the complex 0, the polynomial 0, the function 0 and so on. So the precise question is which 0 are you talking about.

But it looks like your question is more philosophical than mathematical. 0 is merely a symbol that conveys different meaning in different contexts. Obviously since it conveys meanings, it is not worthless. i hope it is right.