Way to evaluate D[(1-x^2)y''[x],{x,n}] ?

*To*: mathgroup at smc.vnet.net*Subject*: [mg14914] Way to evaluate D[(1-x^2)y''[x],{x,n}] ?*From*: Dr Phillip Kent <p.kent at ic.ac.uk>*Date*: Wed, 25 Nov 1998 17:48:35 -0500*Organization*: Imperial College*Sender*: owner-wri-mathgroup at wolfram.com

I'm wondering if and how to make Mathematica evaluate derivatives like D[(1-x^2)y''[x],{x,n}] y[x] is an unspecified function, n is a +ve integer. It seems as though the system ought to "know" that this reduces to three terms only, provided that n is constrained? -Phillip ----------------------------------+---------------------------- Dr Phillip Kent | tel: +44 (0)171 594 8503 The METRIC Project | fax: +44 (0)171 594 8517 Mathematics Department | Imperial College | p.kent at ic.ac.uk London SW7 2BZ, U.K. | http://metric.ma.ic.ac.uk/ ----------------------------------+---------------------------- "Behaviour can be understood only as the history of behaviour"

**Follow-Ups**:**Re: Way to evaluate D[(1-x^2)y''[x],{x,n}] ?***From:*Jurgen Tischer <jtischer@col2.telecom.com.co>