Clarification with divisibility

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tonyc1970
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Clarification with divisibility

Postby tonyc1970 » Sun Sep 15, 2013 6:10 pm

In the text book, "Discrete Mathematics with Applications" the book, on page 172 (for anyone who has the book), makes a statement, "be sure to avoid things like 4 | (3 + 5) = 4 | 8. If read out loud, this becomes, '4 divides the quantity 3 plus 5 equals 4 divides ,' which is nonsense."

Can someone clarify this statement for me?

Thanks,

Tony

nona.m.nona
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Re: Clarification with divisibility

Postby nona.m.nona » Sun Sep 15, 2013 8:35 pm

I believe the intended point is that one may say that two statements have the same or similar meaning, but without using a mathematical operator such as the "equals" sign. For instance, one could say that "Obama was elected in 2008 and again in 2012" is a true statement, and that another way of saying this might be "Obama was a two-term president". But it would be nonsensical to say "Obama was elected in 2008 and again in 2012 = Obama was a two-term president".

The statement is an encouragement to use mathematical notation, and English, in proper ways. The "equals" sign should be used between two expressions which are mathematically equal, not thrown in, willy-nilly, any time two items are related, or merely because one might logically follow from the other.

tonyc1970
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Joined: Fri Aug 02, 2013 4:58 pm
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Re: Clarification with divisibility

Postby tonyc1970 » Sun Sep 15, 2013 9:00 pm

Hi nona.m.nona,

Thanks for your reply. I have read over your explanation and I believe I understand what you mean.

Tony


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