Re: Using Coefficient on an equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg95440] Re: [mg95433] Using Coefficient on an equation*From*: DrMajorBob <btreat1 at austin.rr.com>*Date*: Mon, 19 Jan 2009 02:54:12 -0500 (EST)*References*: <200901181033.FAA13999@smc.vnet.net>*Reply-to*: drmajorbob at longhorns.com

f = a*x^2 + b*x + c == 0; First@Coefficient[f, x^2] a or Coefficient[First@f, x^2] a Bobby On Sun, 18 Jan 2009 04:33:11 -0600, <carlos at colorado.edu> wrote: > If f=a*x^2+b*x+c, Coefficient[f,x^2] obviously returns a. > But if f=a*x^2+b*x+c==0, it returns 0. > > The problem arose using the Calculus`VariationalMethods` package. > It (unfortunately) returns the Euler-Lagrange equations as > such, so I have to remove the useless ==0 appendage for > Coefficient to work properly. Is there a simple direct way out? > -- DrMajorBob at longhorns.com

**References**:**Using Coefficient on an equation***From:*carlos@colorado.edu