Re: Problem with Limit
- To: mathgroup@smc.vnet.net
- Subject: [mg12540] Re: [mg12496] Problem with Limit
- From: Sean Ross <seanross@worldnet.att.net>
- Date: Sat, 23 May 1998 18:11:05 -0400
- References: <199805191731.NAA03571@smc.vnet.net.>
Michel Gosse wrote:
>
> Hello
> With mathematica 3.01, the following command :
> Limit[Log[x]/(x-1)^3,x->0,Direction->-1] produce the error message :
> Take::"take":
> "Cannot take positions 1 through 3 in {-1,1} What is wrong ? Is
> this a bug ?
> Regards
The problem is that Log[x] for x<0 is complex so that the function does
not approach a limit nicely from the negative side. If you help
mathematica out by telling it that you only want to examine the real
part of Log[x]/(x-1)^3, it finds the limit from the negative side just
fine:
Limit[Re[Log[x]/(x-1)^3],x->0,Direction->-1]
returns Infinity.
- References:
- Problem with Limit
- From: michel.gosse@hol.fr (Michel Gosse)
- Problem with Limit