Re: How to use "Apply" to do differentiation ?

*To*: mathgroup at smc.vnet.net*Subject*: [mg114511] Re: How to use "Apply" to do differentiation ?*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Sun, 5 Dec 2010 21:59:16 -0500 (EST)

x^5//FullForm Power[x,5] Apply did what it is supposed to do, it replaced Power with D[#,x]& Use D[#,x]&[x^5] 5*x^4 See http://reference.wolfram.com/mathematica/ref/Function.html Bob Hanlon ---- Mayasky <alix.zhang at gmail.com> wrote: ============= Something simple yet unbelievable occurred when I use: Apply[D[#, x] &, x^5] The output is invariably 1 whether I use x^5 or x^100. Also I suggest you to try "Trace" command to see the weirdness -- the output is messy if pasted as text here. Finally I have to take a detour and use: Nest[D[#, x] &, x^5, 1] I have been using Mathematica for several years and never found that. I myself is wordless, but can anyone explain that?