First, brush up the notion of sets. For example:
http://en.wikipedia.org/wiki/Set_%28mathematics%29
The intersection of two sets A and B is written as:
A∩B
Set A could be defined as :{1,2,3,4,5}
and set B could be defined as:{2,4,6,8,10)
The intersection of sets A and B, A∩B, is another set containing members which are present in both A and B, namely A∩B={2,4}.
So whis is the intersection of the set of primes less than 30,
P={2,3,5,7,11,13,17,19,23,29}
and the set of all positive odd numbers,
Q={1,3,5,7,9,11,13,15,17,19,21,23,25,27,29,31,33,35,37,....ad infinitum}
So what is P∩Q?
Post what you think.