Xref: utzoo rec.humor:10884 sci.misc:1144 Path: utzoo!mnetor!uunet!husc6!rutgers!iuvax!pur-ee!pur-phy!hal From: hal@pur-phy (Hal Chambers) Newsgroups: rec.humor,sci.misc Subject: Re: Do You Have an Interesting Formula? Message-ID: <1029@pur-phy> Date: 24 Mar 88 12:28:41 GMT References: <2933@slovax.UUCP> <3451@bnrmtv.UUCP> <9@dm.sei.cmu.edu> <238@scampi.UUCP> Reply-To: hal@newton.physics.purdue.edu.UUCP (Hal Chambers) Organization: Purdue Univ. Physics Dept., W. Lafayette, IN Lines: 30 In article <238@scampi.UUCP> ramin@scampi.UUCP (Fubar Void) writes: >In article <9@dm.sei.cmu.edu>, ejh@sei.cmu.edu (Erik Hardy) writes: >> on a lighter note, what's the value of: >> >> -- cabin >> | 1 >> | - dx? >> | x >> -- 1 >I think it's more like: > -- infinity > | 1 > | --------- d(cabin) = log(cabin) + C > | cabin > -- 0 Wrong! This ( ^ ) integral blows up! On the RHS the "log(cabin)" term must be evaluated at both infinity and 0; log is unbounded in both places. Even the integrand is unbounded at 0! Also the integrand, 1/x, does not go to zero fast enough in the positive direction for the integral to be bounded. Consider the integer sum: SUM(1/n) for n = 1,....,infinity This is unbounded even though the discrete sum contains many fewer values than the Riemann Sum (i.e. integral). Hal (I probably spelled Riemann wrong) Chambers