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#1 09. 07. 2016 08:58

stuart clark
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summation of function

If $f(x)$ is a differentiable function from $\mathbb{R}\rightarrow \mathbb{Q}\;,$ Then $\sum^{100}_{r=0}(-1)^rf(r)$

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#2 13. 07. 2016 11:11 — Editoval vanok (13. 07. 2016 11:12)

vanok
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Re: summation of function

Hi,
To solve this exercise, you can use three theorems
1) Any differentiable function of one real variable is a  is continuous
2) Intermediate value theorem
3) Any continuons function $f:\mathbb{R}\rightarrow \mathbb{Q}\;$ is a constant function. (Theorem 3) is deducted from the theorem 2))
Answer


Remark, it is better to write f, for a function, and not f (x).


Srdecne Vanok
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Do not judge the other one.
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#3 18. 07. 2016 10:35

stuart clark
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Re: summation of function

Thanks ↑ vanok: got it.

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