       Re: NDSolve with NIntegrate where Integral is a function of x

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• Subject: [mg127377] Re: NDSolve with NIntegrate where Integral is a function of x
• From: Bob Hanlon <hanlonr357 at gmail.com>
• Date: Fri, 20 Jul 2012 03:54:53 -0400 (EDT)
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```You did not specify g[x,t] so I could not verify that this will work.

You also need to pay closer attention to syntax.

h[x_?NumericQ] := Integrate[g[x, t], {t, 0, Infinity}]

NDSolve[{y'[x] == f[x]*h[x], y == 0.04}, y[x], {x, 0, 10}]

Bob Hanlon

On Thu, Jul 19, 2012 at 3:50 AM, Nikthecrab <nikhil.dexter at gmail.com> wrote:
> I am trying to solve a differential equation using NDSolve . It is of the form:
>
> NDSolve[{y'[x]=f(x)*Integrate[g(x,t),{t,0,infinity}],y=0.04},y[x],{x,0,10}]
>
> here f is a function of x and g is a function of x and a dummy variable t for integration.
> The integral cannot be solved directly in terms of x.So I tried using NIntegrate.But NIntegrate requires x to be a number while NDSolve clearly has to vary x from 0 to 10. Can anyone suggest a suitable solution to this problem?
>

```

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