Limit fails !
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Arnaud Usciati
Apr 11, 2015, 8:22:32 AM4/11/15
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Hello,
I found 2 issues with limit().
x = symbols("x", real=True)
f = Lambda(x, (x+exp(x))/(x-1))
Input : limit(f(x), x, -oo, '+')
Output : 0 --> Wrong
Input : limit(expand(f(x)), x, -oo, '+')
Output : 1 --> Correct
g = Lambda(x, (ln(x)-1)**(1-sqrt(x)))
Input : limit(g(x), x, E, '+')
Ouput : 0 --> Wrong
The correct value is +oo !
Python 3.4.2 (v3.4.2:ab2c023a9432, Oct 6 2014, 22:15:05) [MSC v.1600 32 bit (Intel)] on win32
Arnaud.
Sergey B Kirpichev
May 3, 2015, 7:26:09 PM5/3/15
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FYI, this was fixed here: https://github.com/skirpichev/omg
In [1]: limit((x + exp(x))/(x - 1), x, -oo)
Out[1]: 1
In [2]: limit((ln(x) - 1)**(1 - sqrt(x)), x, E)
Out[2]: ∞
In [1]: limit((x + exp(x))/(x - 1), x, -oo)
Out[1]: 1
In [2]: limit((ln(x) - 1)**(1 - sqrt(x)), x, E)
Out[2]: ∞
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