Problem with "Which"

*To*: mathgroup at smc.vnet.net*Subject*: [mg122204] Problem with "Which"*From*: mbmb <sb at 9y.com>*Date*: Thu, 20 Oct 2011 07:44:54 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

Who can check my module? KD[f0_, a0_, b0_] := Module[{f = f0, a = a0, b = b0}, f2 = D[f, {x, 2}]; ew = Solve[D[f, x] == 0, x, Reals]; Print["Extremwerte: ", {Which[f2 > 0, "T", f2 < 0, "H", f2 = 0, "S" ], x, f} /. ew]; Print["Extremwerte: ", {If[f2 > 0, "T", "H" ], x, f} /. ew]; ] When I enter: KD[x^3 - 3 x^2, -1, 4] the output is Extremwerte: {{Which[-6+6 x<0,H,f2=0,S],0,0},{T,2,-4}} whereas the IF-line gives Extremwerte: {{H,0,0},{T,2,-4}} Why can't I use Which in this case. Why doesn't Mathematica evaluate f2 in all cases?

**Follow-Ups**:**Re: Problem with "Which"***From:*DrMajorBob <btreat1@austin.rr.com>

**Re: Problem with "Which"***From:*DrMajorBob <btreat1@austin.rr.com>