Re: Initial condition with DSolve in Mathematica 8 doesn't work
- To: mathgroup at smc.vnet.net
- Subject: [mg116003] Re: Initial condition with DSolve in Mathematica 8 doesn't work
- From: Bert RAM Aerts <bert.ram.aerts at gmail.com>
- Date: Sat, 29 Jan 2011 05:24:15 -0500 (EST)
- References: <ihu8f1$1lc$1@smc.vnet.net>
After restarting Mathematica 8.0.0 Home Edition (on Mandriva Linux
2010.2 x86_64) the command suddenly started working just fine.
I have no clue why it at first did not work...
On 28 jan, 12:14, Bert RAM Aerts <bert.ram.ae... at gmail.com> wrote:
> When I enter the following in Mathematica 8.0.0 Home Edition:
> DSolve[{y'[x] + y[x] == a Sin[x], y[0] == 0}, y[x], x]
> I get
> DSolve::deqn: Equation or list of equations expected instead of True
> in the first argument {y[x]+(y^\[Prime])[x]==a Sin[x],True}. >>
>
> The initial condition becomes a "True"...
>
> In Mathematica 7.0.1 Home Edition, this same input gives the expected
> output:
> {{y[x] -> -(1/2) a E^-x (-1 + E^x Cos[x] - E^x Sin[x])}}
>
> What am I missing?