Question

nat I &0, then at 0 l c and i c l< b imply c = 0 (5) Show that a set of integers closed under addition need not consist of all multiples of a single fixed element. (6) Show that any two integers a and b have a least common multiple m a, b which is a divisor of every common multiple of a and b and which is itself a common multiple of a and b. (Hint: see if you can adapt the proof given for the existence of greatest common divisors.)

Answer 1

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