### Author Topic: A simple problem  (Read 1737 times)

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#### AngelFish

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##### A simple problem
« on: September 23, 2011, 04:42:55 am »
Here's a little problem I noticed today that's quite easy for humans to solve, but is surprisingly difficult to get from a computer.

LimN→∞ e-XN = f(x)

The challenge is to get a computer system to properly determine f(x) [after you solve it for yourself first].

Spoiler For Symbolic answer for humans:
It's the Boxcar function with limits of (-1,1).
« Last Edit: September 23, 2011, 04:45:32 am by Qwerty.55 »
∂²Ψ    -(2m(V(x)-E)Ψ
---  = -------------
∂x²        ℏ²Ψ

#### phenomist

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##### Re: A simple problem
« Reply #1 on: September 23, 2011, 07:32:14 pm »
Also note that f(1)=e
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#### sqrt(Time)

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##### Re: A simple problem
« Reply #2 on: September 24, 2011, 12:41:07 pm »
Wouldn't f(x) be undefined for any x>=1? As you take it to successive powers, it alternates wildly between negative infinity and positive infinity (or at least negative one and positive one), so the limit wouldn't exist.. or am I missing something? :-/