RE: Coefficient problem
- To: mathgroup at smc.vnet.net
- Subject: [mg36435] RE: [mg36421] Coefficient problem
- From: "DrBob" <drbob at bigfoot.com>
- Date: Sat, 7 Sep 2002 02:53:41 -0400 (EDT)
- Reply-to: <drbob at bigfoot.com>
- Sender: owner-wri-mathgroup at wolfram.com
This works: eq = a x^2 + b x + c discriminant[eq_, x_] := Coefficient[eq, x]^2 - 4 Coefficient[eq, x, 2] Coefficient[eq, x, 0] discriminant[eq, x] x^0 is reduced to 1 and the Coefficient of 1 doesn't make sense to Mathematica, because it depends on what the variable is (a, b, c, or x?). So, the other form of the Coefficient call is needed. I used it for the second power too, but that wasn't necessary. I think that form is best, though, since it allows no ambiguity. I renamed the function because that's what the quantity is often called, for a quadratic. Bobby Treat -----Original Message----- From: CeZaR [mailto:pascal at go.ro] To: mathgroup at smc.vnet.net Subject: [mg36435] [mg36421] Coefficient problem Hi, Now I'm trying to calculate this formula: Delta[eq_, x_]:=Coefficient[eq, x]^2 - 4 Coefficient[eq, x^2] Coefficient[eq, x^0] eq has this form a x^2 + b x + c But there is a problem with the x^0 coefficient! How can I overcome that? Thanks! CeZaR