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Discrete math - proof of divisibility question

  • Thread starter dgamma3
  • Start date
  • #1
12
0
is this true or false:

If a|b and a|c, then one (or both) of b|c or c|b holds.

if I want to disprove this, can I:

let a = 5, x = 2 and y = 3.

b=ax
c=ay

then c=bz
and c = bg doesn't hold.
 

Answers and Replies

  • #2
Bacle2
Science Advisor
1,089
10
Why make it so complicated? You constructed a counter-example:

a=5 , b=10 c=15 , and neither 10|15 nor 15|10.
 

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