设 a=kx,b=ky。则 gcd,\text{lcm}(a, b) = kxy。所以 \gcd(a, b) \times \text{lcm}(a, b) = k^2 x y = a \times b。
设 a=kx,b=ky。则 gcd,\text{lcm}(a, b) = kxy。所以 \gcd(a, b) \times \text{lcm}(a, b) = k^2 x y = a \times b。