Re: Integral confusion
- To: mathgroup at smc.vnet.net
- Subject: [mg107279] Re: Integral confusion
- From: Peter Breitfeld <phbrf at t-online.de>
- Date: Mon, 8 Feb 2010 03:32:57 -0500 (EST)
- References: <hkm7d8$os0$1@smc.vnet.net>
Jon Joseph wrote: > All: Is this integral wrong? If not could someone explain the minus sign > inside the log? > > Integrate[1/(x + 1) - 1/(x + 6), x] // Simplify > > log(-2 (x + 1)) - log(2 (x + 6)) > > Thanks, Jon.= > No, it's not wrong, because if you take the derivative of the result you get your integrand back. It only differs from the result you get by calculating the integral "by hand" by the constant log(-2)-log(2), so it is a valid "stammfunktion" (German, how do you call that in English? antiderivative?) -- _________________________________________________________________ Peter Breitfeld, Bad Saulgau, Germany -- http://www.pBreitfeld.de