Definition of common multiples: The common multiples of two or more integers are called their common multiples. The least common multiple of two or more integers is called their least common multiple.
A number has countless multiples, which means that the set of multiples of a number is infinite. Note: you can't call a number a multiple alone, you can only say who is a multiple of who.
Extended data:
law
The square difference of any two odd numbers is a multiple of 8.
Prove: Let any odd number 2n+ 1, 2m+ 1, (m, n∈N).
(2m+ 1)2-(2n+ 1)2
=(2m+ 1+2n+ 1)*(2m-2n)
=4(m+n+ 1)(m-n)
When both m and n are odd or even, m-n is even and divisible by 2.
When m and n are odd and even, m+n+ 1 is even and divisible by 2.
So (m+n+ 1)(m-n) is a multiple of 2.
Then 4(m+n+ 1)(m-n) must be a multiple of 8 (note: 0 can be divisible by 2, so 0 is an even number, and 0 can also be divisible by 8, so 0 is a multiple of 8. )
References:
Baidu Encyclopedia-Multiply