FourierTransform bug?

• To: mathgroup at smc.vnet.net
• Subject: [mg44126] FourierTransform bug?
• From: "Dr. Wolfgang Hintze" <weh at snafu.de>
• Date: Thu, 23 Oct 2003 07:15:54 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

```Hi all,
What happens here in Mathematica 4.0?

The sum of two terms is not correctly Fourier-transformed

In[46]:=
FourierTransform[q + p*Exp[-(I*t*v)], t, x]

Out[46]=
0

But each term separately is ok:

In[57]:=
xx = FourierTransform[q, t, x]

Out[57]=
Sqrt[2*Pi]*q*DiracDelta[x]

In[48]:=
yy = FourierTransform[p*Exp[-I*t*v], t, x]

Out[48]=
p*Sqrt[2*Pi]*DiracDelta[v - x]

In[49]:=
xx + yy

Out[49]=
p*Sqrt[2*Pi]*DiracDelta[v - x] +
Sqrt[2*Pi]*q*DiracDelta[x]

If instead of the Exp[] function we take powers of t it works fine as well:

In[63]:=
FourierTransform[q + p*t, t, x]

Out[63]=
Sqrt[2*Pi]*q*DiracDelta[x] - I*p*Sqrt[2*Pi]*
Derivative[1][DiracDelta][x]

Any hint is greatly appreciated,

Wolfgang

```

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