Same Limit: OK in 5.2, fails in 6.0; Packages gone in 6.0 ???

*To*: mathgroup at smc.vnet.net*Subject*: [mg77959] Same Limit: OK in 5.2, fails in 6.0; Packages gone in 6.0 ???*From*: jrc <jrchaff at mcn.net>*Date*: Wed, 20 Jun 2007 05:41:19 -0400 (EDT)

Why? I have, $Assumptions = {a > 0, k1 > 0, k2 >0, x e(in) Reals} (repeats ok) i1b = (1/a)* Integral from -a/2 to +a/2 of integrand: exp(- i k2 x) exp(i k1 x) dx with the expected result, i1b = fraction with numerator = 2 Sin[(1/2)a(k1-k2)] and denominator = a(k1-k2) Now I want the limit of this result, as the parameter a goes to infinity: Limit[i1b, a -> Infinity] Mathematica 5.2 gives correct result, zero; (note this is just lim(sin(x)/x, x -> inf), which is obviously zero) Mathematica 6.0 is unable to evaluate the limit. Ruskeepaa's "Navigator", 2nd ed, (written for v5.2) claims there is a package, "Calculus`Limit`" that makes 'Limit' work better (p. 395 and p. 430). However, no such package seems to exist in v6.0. How many packages no longer exist in 6.0 ???? Is there a list ???? Can anyone give me a reason for this obvious failure? jrc

**Follow-Ups**:**Re: Same Limit: OK in 5.2, fails in 6.0; Packages gone***From:*Daniel Lichtblau <danl@wolfram.com>

**Re: Same Limit: OK in 5.2, fails in 6.0; Packages gone***From:*Carl Woll <carlw@wolfram.com>

**Re: Same Limit: OK in 5.2, fails in 6.0; Packages gone in 6.0 ???***From:*Andrzej Kozlowski <akoz@mimuw.edu.pl>