Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

in reality, all of this has been a total load of old bollocks
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C
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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 21 Jun 2018, 07:45

Pansy Puff wrote:They are both countable and can be put in a one to one correspondence so they are the same size of infinity. But the set of real numbers is uncountable and hence a larger infinity.


Oh no!

I can feel Hilbert's Hotel paradox looming.....!!

https://en.wikipedia.org/wiki/Hilbert%2 ... rand_Hotel






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neville harp wrote:God bless you brother C x

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Positive Passion » 21 Jun 2018, 17:46

Pansy Puff wrote:
NMB wrote:
Pansy Puff wrote:And the set of rational numbers is the same size as the set of integers!


Only in the sense that they’re both infinite. Else to disprove it, all integers are rational. 1/2 is rational but not integer. So number of rationals must be at least number of integers plus 1.

An example to show the problem with your disproof.

The set S ={1, 2, 3,...} is infinite in size. If I remove all the odd numbers then surely I have a set of numbes that is smaller,
E ={2, 4, 6, ...} .After all, I have removed every other number.

But if I take set S and double every number then I get the same set of numbers E ={2, 4, 6...} But if I doubled every number the set must be the same size as S.

So I have shown that S and E are the same size, and that S is "twice as big" as E.


Huh? Surely half infinity is still infinity. As is twice inifinity.

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby Pansy Puff » 21 Jun 2018, 21:37

Positive Passion wrote:
Pansy Puff wrote:
NMB wrote:
Only in the sense that they’re both infinite. Else to disprove it, all integers are rational. 1/2 is rational but not integer. So number of rationals must be at least number of integers plus 1.

An example to show the problem with your disproof.

The set S ={1, 2, 3,...} is infinite in size. If I remove all the odd numbers then surely I have a set of numbes that is smaller,
E ={2, 4, 6, ...} .After all, I have removed every other number.

But if I take set S and double every number then I get the same set of numbers E ={2, 4, 6...} But if I doubled every number the set must be the same size as S.

So I have shown that S and E are the same size, and that S is "twice as big" as E.


Huh? Surely half infinity is still infinity. As is twice inifinity.

Which infinity are you talking about? Some infinities are bigger than others.

https://en.wikipedia.org/wiki/Aleph_number
“He’s got the memory of an elephant ... and the trophy cabinet of one too.”

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby NMB » 21 Jun 2018, 23:26

Pansy Puff wrote:
Positive Passion wrote:
Pansy Puff wrote:An example to show the problem with your disproof.

The set S ={1, 2, 3,...} is infinite in size. If I remove all the odd numbers then surely I have a set of numbes that is smaller,
E ={2, 4, 6, ...} .After all, I have removed every other number.

But if I take set S and double every number then I get the same set of numbers E ={2, 4, 6...} But if I doubled every number the set must be the same size as S.

So I have shown that S and E are the same size, and that S is "twice as big" as E.


Huh? Surely half infinity is still infinity. As is twice inifinity.

Which infinity are you talking about? Some infinities are bigger than others.

https://en.wikipedia.org/wiki/Aleph_number


So my infinity plus one can be bigger than your infinity and my disproof stands.
turn on, tune in, nod off

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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 24 Jun 2018, 13:31

7 is three-and-a-half times greater than 2

The product of 2 and 3.5 is 7

7 divided by 2 is 3.5

2 lots of 3.5 is 7








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Re: Maths is not elitist or difficult - HAVE A GO!! Say something about 7 and 2

Postby C » 27 Jun 2018, 15:37

7 is odd

2 is even






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neville harp wrote:God bless you brother C x