It seems strange?+x+x .(x times)=x^2 then x=2x(differentiate wrt x)?

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The discussion centers on the mathematical expression of summing a variable \( x \) repeated \( x \) times, leading to the equation \( x+x+\ldots+x = x^2 \). It concludes that this expression only holds true when \( x \) is a natural number, as differentiating with respect to \( x \) is invalid in non-natural domains. The participants emphasize that attempting to apply derivatives to such expressions results in nonsensical conclusions, particularly when considering non-integer values like \( \sqrt{2} \).

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It seems strange?+x+x...(x times)=x^2 then x=2x(differentiate wrt x)?

x+x=2x
x+x+x=3x
x+x+x+x=4x
...
x+x+x+x+x+x+...(n times)=nx
x+x+x+x+x+x+...(x times)=x*x=x2
differentiate both sides with respect to x;
1+1+1+1+1+1...(x times)=2x
x=2x(what is it?)
what's wrong?
 
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Saying x+x+x+x+x+x+...+x (x times) simply makes no sense. It only makes sense if x is a natural number.

What, for example, is

[tex]\sqrt{2}+\sqrt{2}+...+\sqrt{2}~~(\sqrt{2}~ \text{times})[/tex]

The expression makes no sense.

It only makes sense for natural numbers. And if the domain is only the natural numbers, then we can take no derivative.
 


micromass said:
Saying x+x+x+x+x+x+...+x (x times) simply makes no sense. It only makes sense if x is a natural number.

What, for example, is

[tex]\sqrt{2}+\sqrt{2}+...+\sqrt{2}~~(\sqrt{2}~ \text{times})[/tex]

The expression makes no sense.

It only makes sense for natural numbers. And if the domain is only the natural numbers, then we can take no derivative.
Wow fantastic...
If domain is natural number then the curve will not remain continuous and their is nothing like derivative for such function.
thanks...
 

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