a|n ==> n = 0 mod a
b|n ==> n = 0 mod b
n = 0 mod (a*b) since gcd(a,b) = 1
that means ab|n ......proved
+++++++++++=
b|n ==> n = 0 mod b
n = 0 mod (a*b) since gcd(a,b) = 1
that means ab|n ......proved
+++++++++++=
-
if a|n then a = jn for integer j.
if b|n then b = kn for integer k.
therefore ab|n → (jn)(kn)|n → jkn²|n = true.
if b|n then b = kn for integer k.
therefore ab|n → (jn)(kn)|n → jkn²|n = true.