Does ab ≡ 0 (mod m) imply a|m or b|m?

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The discussion centers on the modular arithmetic expression ab ≡ 0 (mod m) and whether it implies that either a divides m or b divides m. It is established that this implication is false, with the example of a = 8, b = 9, and m = 12 demonstrating that neither 8 nor 9 divides 12, despite the product ab being congruent to 0 modulo m.

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imagination10
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ab ≡ 0 (mod m), where a and b are positive integer < m.
Does it follow that either a| m or b| m?


Can anyone give a proof for this ?
 
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Not true. Example: a=8, b=9, m=12.
 

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