is 1 a composite number or a prime number?

4 answers

prime.
how do u know?
good question. That is the way I learned it, years ago. Now that I look, I am wrong, it has been redefined. Thanks for asking.

Under current definitions, 1 is neither prime nor composite.
Read this:
http://en.wikipedia.org/wiki/Composite_number
and
http://en.wikipedia.org/wiki/Prime_number