On 20-9-2011 22:27, Darren New wrote:
> On 9/20/2011 1:08, Invisible wrote:
>> On 20/09/2011 02:06 AM, Darren New wrote:
>>> On 9/19/2011 11:20, Orchid XP v8 wrote:
>>>> Fact is, 0 * infinity = 0, so it's not a sensible answer.
>>>
>>> I can't imagine how you can say dividing by zero is undefined, but then
>>> go and define multiplying zero by infinity. :-)
>>
>> If you multiply *anything* by zero, the result is always zero.
>
> No it isn't, if you don't take into account the existence of infinity.
>
>> pre-existing definition of how multiplication by zero works.
>
> The "pre-existing definition" doesn't take into account infinity.
>
> Yes, multiplying any real number by zero gives you zero. That isn't
> saying anything about infinity.
>

Put another way: multiplying any number by zero gives zero, multiplying 
any number by infinity gives infinity (give or take a sign)

Hence 0 * infinity is both zero and infinity.
Or actually it isn't, it is undefined.

The actual rules are:
multiplying any *finite* number by zero gives zero,
multiplying any *non-zero, positive* number by infinity gives infinity

-- 
Apparently you can afford your own dictator for less than 10 cents per 
citizen per day.

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