Number Theory: Divisibilty

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Q: Prove that if a and b are positive integers satisfying (a,b)=[a,b}, then a=b.

My approach (with ans): (a,b) means gcd, and I let g=(a,b) since g is the gcd, then I get these two: g|a and g|b, while g

Next is [a,b], the lcm of a and b, and I let it be h. then I get another two of these: a|h and b|h while a

Combine the inequalities together will get: g

Since the question provides that g=h, so h

Is the a correct explanation? As I hope to get full credits, I hope I can present my answers as detail as possible (without any faults). Thank you.