Is Zero x Infinity Really a Real Number?

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SUMMARY

The discussion centers on the mathematical expression of zero multiplied by infinity (0 × ∞) and its classification as an indeterminate form. Participants argue that while zero times any finite number is definitively zero, the multiplication of zero by infinity leads to undefined results depending on the context, particularly in calculus and limits. The conversation highlights the necessity of defining multiplication in the context of real numbers and the implications of treating infinity as a quantity. Ultimately, the consensus is that 0 × ∞ cannot be simplistically defined as zero without considering the broader mathematical framework.

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  • #61
Bipolar Demon said:
Isnt multiplication just glorified addition? so according to my primitive views,=) if so how you can keep adding zero infinitely to get zero IMO.

Sometimes primitive ideas are the most informative.

I could see defining ## x * \infty = x + x+ x + \cdots ## i.e an infinite sequence. Perhaps this has already been said in this thread in a different way.

-Dave K
 
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  • #62
dkotschessaa said:
Sometimes primitive ideas are the most informative.

I could see defining ## x * \infty = x + x+ x + \cdots ## i.e an infinite sequence. Perhaps this has already been said in this thread in a different way.

-Dave K

yes but that series it would (?) seem to diverge to infinity or minus infinity, and converge to zero if x=0. IIRC
 
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  • #63
this man HATES much of set theory and calculus, and real numbers...very interesting debate:





 
  • #64
Bipolar Demon said:
yes but that series it would (?) seem to diverge to infinity or minus infinity, and converge to zero if x=0. IIRC

Well, that's would I would expect it to do!
 
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  • #65
Bipolar Demon said:
this man HATES much of set theory and calculus, and real numbers...very interesting debate:



Yeah, there are some.

I've considered being a finitist if only to be contrary.
 
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