Two or more integers are coprime if they have no positive factors in common other than \(1\).
There are lots of ways used to say or write this:
- \(a\) is coprime to \(b\).
- \(a\) is relatively prime to \(b\).
- \(a\) is mutually prime to \(b\).
- \(\mathop{\mathrm{hcf}}(a,b) = 1\).
- \(\gcd(a,b) = 1\).
- \(a \perp b\).
For example, \(14\) and \(15\) are coprime to each other as \(14 = 2 \times 7\) and \(15 = 3 \times 5\): they have no positive common factors other than \(1\).
