Re: Integrate bug
- To: mathgroup at smc.vnet.net
- Subject: [mg108269] Re: Integrate bug
- From: "Alexey Popkov" <lehin.p at gmail.com>
- Date: Fri, 12 Mar 2010 07:10:14 -0500 (EST)
- References: <hnakk1$5sg$1@smc.vnet.net>
Interestingly, Mathematica 5.2 gives right answer:
In[1]:=
Integrate[1/(6 (4 - Y)^(1/3)), {Y, -4, 4}]
Out[1]=
1
"Daniel" <daniel.ernesto.acuna at gmail.com> ÓÏÏÂÝÉÌ/ÓÏÏÂÝÉÌÁ × ÎÏ×ÏÓÔÑÈ
ÓÌÅÄÕÀÝÅÅ: news:hnakk1$5sg$1 at smc.vnet.net...
> Hello,
>
> I was working with the following probability distribution
>
> P(Y) = 1/(6 (4 - Y)^(1/3)), for -4 < Y < 4
>
> and I tried to check whether it would sum up to 1. But it didn't work
> with Integrate:
>
> Integrate[1/(6 (4 - Y)^(1/3)), {Y, -4, 4}] = 0
>
> Clearly, the integral is 1. It is surprising that NIntegrate gives the
> right answer:
>
> NIntegrate[1/(6 (4 - Y)^(1/3)), {Y, -4, 4}] = 1.
>
> Wolfram Alpha seems to have the bug as well:
>
> http://www.wolframalpha.com/input/?i=integrate+1%2F%286+%284+-+Y%29%5E%281%2F3%29%29+from+-4+to+4
>
> Cheers,
> Daniel
>